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    <link:label id="lab_us-gaap_DebtInstrumentCarryingAmount_0FAFD0FC228424426A81F56F55A03707_verboseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount_0FAFD0FC228424426A81F56F55A03707" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Outstanding borrowings</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentCarryingAmount_0FAFD0FC228424426A81F56F55A03707_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount_0FAFD0FC228424426A81F56F55A03707" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Gross</link:label>
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    <link:label id="lab_us-gaap_LineOfCredit_85C65F76A82D754B0EEFF56F55A08FE7_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCredit_85C65F76A82D754B0EEFF56F55A08FE7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount utilized to support the issuance of letters of credit</link:label>
    <link:label id="lab_us-gaap_LineOfCredit_85C65F76A82D754B0EEFF56F55A08FE7_label_en-US" xlink:label="lab_us-gaap_LineOfCredit_85C65F76A82D754B0EEFF56F55A08FE7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Line of Credit</link:label>
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    <link:label id="lab_us-gaap_LineOfCreditFacilityAverageOutstandingAmount_E8AE15666EA363DDE2DAF56F55A0E1AE_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityAverageOutstandingAmount_E8AE15666EA363DDE2DAF56F55A0E1AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Average borrowings during period</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityAverageOutstandingAmount_E8AE15666EA363DDE2DAF56F55A0E1AE_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityAverageOutstandingAmount_E8AE15666EA363DDE2DAF56F55A0E1AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Average Outstanding Amount</link:label>
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    <link:label id="lab_ati_ChangeinContractwithCustomerCurrentAssetRollForward_DEBCB0236472890DED9FFDDA45F4B87A_terseLabel_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerCurrentAssetRollForward_DEBCB0236472890DED9FFDDA45F4B87A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contract Assets, Current [Roll Forward]</link:label>
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    <link:label id="lab_us-gaap_ContractWithCustomerAssetNetCurrent_B88BE4BCA5013D150AC1FDDA45F413ED_periodStartLabel_en-US" xlink:label="lab_us-gaap_ContractWithCustomerAssetNetCurrent_B88BE4BCA5013D150AC1FDDA45F413ED" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance as of January 1, 2018</link:label>
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    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerAssetCurrentPeriodIncrease" xlink:label="loc_ati_ContractwithCustomerAssetCurrentPeriodIncrease_565CD59A4C9704215911FDDA46030B14" xlink:type="locator" />
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    <link:label id="lab_ati_ContractwithCustomerAssetCurrentReclassifiedtoReceivable_75D9E5690EADA03A8043FDDA4603B250_negatedTerseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetCurrentReclassifiedtoReceivable_75D9E5690EADA03A8043FDDA4603B250" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassified to accounts receivable</link:label>
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    <link:label id="lab_ati_ContractwithCustomerAssetCurrentImpairment_BD10F9C2509B5D6D9E1EFDDB64728289_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetCurrentImpairment_BD10F9C2509B5D6D9E1EFDDB64728289" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Impairment</link:label>
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    <link:label id="lab_ati_ContractwithCustomerAssetCurrentReclassification_E9547A99BC838C808DE8FDDA4603E6AD_negatedTerseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetCurrentReclassification_E9547A99BC838C808DE8FDDA4603E6AD" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassification to/from long-term</link:label>
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    <link:label id="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recognized in current year</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783_label_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Nocurrent, Period Increase</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Nocurrent, Period Increase</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerAssetNocurrentPeriodIncrease" xlink:label="loc_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783" xlink:to="lab_ati_ContractwithCustomerAssetNocurrentPeriodIncrease_2EBAA700A0D82CCC1A1BFDDA46037783" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassified to accounts receivable</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C_label_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Noncurrent, Reclassified to Receivable</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Noncurrent, Reclassified to Receivable</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable" xlink:label="loc_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C" xlink:to="lab_ati_ContractwithCustomerAssetNoncurrentReclassifiedtoReceivable_789D83CA15A9819F5D8BFDDA4603D33C" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Impairment</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3_label_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Noncurrent, Impairment</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Noncurrent, Impairment</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerAssetNoncurrentImpairment" xlink:label="loc_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3" xlink:to="lab_ati_ContractwithCustomerAssetNoncurrentImpairment_727CC5A57A141DA489FBFDDC290B59A3" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE_negatedTerseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassification to/from short-term</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE_label_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Noncurrent, Reclassification</link:label>
    <link:label id="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Asset, Noncurrent, Reclassification</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerAssetNoncurrentReclassification" xlink:label="loc_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE" xlink:to="lab_ati_ContractwithCustomerAssetNoncurrentReclassification_EC7A95BF3B7734ACE405FDDA46030EEE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ContractWithCustomerAssetNetNoncurrent_F7380408525993C330D6FDDA4603A0C5_periodEndLabel_en-US" xlink:label="lab_us-gaap_ContractWithCustomerAssetNetNoncurrent_F7380408525993C330D6FDDA4603A0C5" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance as of March 31, 2018</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerAssetNetNoncurrent" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetNoncurrent_F7380408525993C330D6FDDA4603A0C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerAssetNetNoncurrent_F7380408525993C330D6FDDA4603A0C5" xlink:to="lab_us-gaap_ContractWithCustomerAssetNetNoncurrent_F7380408525993C330D6FDDA4603A0C5" xlink:type="arc" />
    <link:label id="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112_terseLabel_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contract Liabilities, Current [Roll Forward]</link:label>
    <link:label id="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112_label_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Change in Contract with Customer, Liability, Current [Roll Forward]</link:label>
    <link:label id="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112_documentation_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Change in Contract with Customer, Liability, Current [Roll Forward]</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ChangeinContractwithCustomerLiabilityCurrentRollForward" xlink:label="loc_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112" xlink:to="lab_ati_ChangeinContractwithCustomerLiabilityCurrentRollForward_6C03EF83FD28A133EDDEFDDA46032112" xlink:type="arc" />
    <link:label id="lab_us-gaap_ContractWithCustomerLiabilityCurrent_669FEE04C9A823680C30FDDA4603538E_periodStartLabel_en-US" xlink:label="lab_us-gaap_ContractWithCustomerLiabilityCurrent_669FEE04C9A823680C30FDDA4603538E" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance as of January 1, 2018</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_669FEE04C9A823680C30FDDA4603538E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerLiabilityCurrent_669FEE04C9A823680C30FDDA4603538E" xlink:to="lab_us-gaap_ContractWithCustomerLiabilityCurrent_669FEE04C9A823680C30FDDA4603538E" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recognized in current year</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D_label_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Period Increase</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Period Increase</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityCurrentPeriodIncrease" xlink:label="loc_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D" xlink:to="lab_ati_ContractwithCustomerLiabilityCurrentPeriodIncrease_94CB4AFF6B0C84F959FFFDDA46032F4D" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts in beginning balance reclassified to revenue</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094_label_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Reclassified to Revenue</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Reclassified to Revenue</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue" xlink:label="loc_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094" xlink:to="lab_ati_ContractwithCustomerLiabilityCurrentReclassifiedtoRevenue_09398F5EB375A00B5B88FDDF0E296094" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current year amounts reclassified to revenue</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA_label_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Revenue Recognized</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Revenue Recognized</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityCurrentRevenueRecognized" xlink:label="loc_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA" xlink:to="lab_ati_ContractwithCustomerLiabilityCurrentRevenueRecognized_C10909C8BE93A3E9507EFDDA46030ECA" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8_label_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Other</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Other</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityCurrentOther" xlink:label="loc_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8" xlink:to="lab_ati_ContractwithCustomerLiabilityCurrentOther_F52295CDB0E6EF13FDF3FDDA4603D4E8" xlink:type="arc" />
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B_negatedTerseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassification to/from long-term</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B_label_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Reclassification</link:label>
    <link:label id="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Current, Reclassification</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityCurrentReclassification" xlink:label="loc_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B" xlink:to="lab_ati_ContractwithCustomerLiabilityCurrentReclassification_523FF20D8BE3C3B3FBBBFDDA4603373B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ContractWithCustomerLiabilityCurrent_7483359E9851C1827573FDDA4603C92D_periodEndLabel_en-US" xlink:label="lab_us-gaap_ContractWithCustomerLiabilityCurrent_7483359E9851C1827573FDDA4603C92D" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance as of March 31, 2018</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_7483359E9851C1827573FDDA4603C92D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerLiabilityCurrent_7483359E9851C1827573FDDA4603C92D" xlink:to="lab_us-gaap_ContractWithCustomerLiabilityCurrent_7483359E9851C1827573FDDA4603C92D" xlink:type="arc" />
    <link:label id="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F_terseLabel_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contract Liabilities, Noncurrent [Roll Forward]</link:label>
    <link:label id="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F_label_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Change in Contract with Customer, Liability, Noncurrent [Roll Forward]</link:label>
    <link:label id="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F_documentation_en-US" xlink:label="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Change in Contract with Customer, Liability, Noncurrent [Roll Forward]</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward" xlink:label="loc_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F" xlink:to="lab_ati_ChangeinContractwithCustomerLiabilityNoncurrentRollForward_0F1707F316EC0D4826A0FDDA4603173F" xlink:type="arc" />
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentPeriodIncrease_6747A2B75B2F138BB038FDDA4603A286_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentPeriodIncrease_6747A2B75B2F138BB038FDDA4603A286" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recognized in current year</link:label>
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentPeriodIncrease_6747A2B75B2F138BB038FDDA4603A286_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentPeriodIncrease_6747A2B75B2F138BB038FDDA4603A286" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Noncurrent, Period Increase</link:label>
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue_0ACB7F4D2A534C8EDB07FDE1F13341B2_terseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentReclassifiedtoRevenue_0ACB7F4D2A534C8EDB07FDE1F13341B2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts in beginning balance reclassified to revenue</link:label>
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentRevenueRecognized_11E537F18981F62E7498FDDA46037BEC_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentRevenueRecognized_11E537F18981F62E7498FDDA46037BEC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Noncurrent, Revenue Recognized</link:label>
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentOther_C1F842344E61F923F049FDDA46032157_negatedTerseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentOther_C1F842344E61F923F049FDDA46032157" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentOther_C1F842344E61F923F049FDDA46032157_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentOther_C1F842344E61F923F049FDDA46032157" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Noncurrent, Other</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityNoncurrentOther" xlink:label="loc_ati_ContractwithCustomerLiabilityNoncurrentOther_C1F842344E61F923F049FDDA46032157" xlink:type="locator" />
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentReclassification_8143D6B3FA772D5284FBFDDA46038F45_negatedTerseLabel_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentReclassification_8143D6B3FA772D5284FBFDDA46038F45" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassification to/from short-term</link:label>
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    <link:label id="lab_ati_ContractwithCustomerLiabilityNoncurrentReclassification_8143D6B3FA772D5284FBFDDA46038F45_documentation_en-US" xlink:label="lab_ati_ContractwithCustomerLiabilityNoncurrentReclassification_8143D6B3FA772D5284FBFDDA46038F45" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract with Customer, Liability, Noncurrent, Reclassification</link:label>
    <link:loc xlink:href="ati-20180331.xsd#ati_ContractwithCustomerLiabilityNoncurrentReclassification" xlink:label="loc_ati_ContractwithCustomerLiabilityNoncurrentReclassification_8143D6B3FA772D5284FBFDDA46038F45" xlink:type="locator" />
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    <link:label id="lab_us-gaap_ContractWithCustomerLiabilityNoncurrent_C0A2D8B2E2181F6A36D6FDDA4603636A_periodEndLabel_en-US" xlink:label="lab_us-gaap_ContractWithCustomerLiabilityNoncurrent_C0A2D8B2E2181F6A36D6FDDA4603636A" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance as of March 31, 2018</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_C0A2D8B2E2181F6A36D6FDDA4603636A" xlink:type="locator" />
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    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentAbstract_902CE0976C7EE6AE80373E655DD727C7_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract_902CE0976C7EE6AE80373E655DD727C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Abstract]</link:label>
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    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_E8F6FF4BC3A5DAF69C9B3E655DD714BC_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_E8F6FF4BC3A5DAF69C9B3E655DD714BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table Text Block]</link:label>
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    <link:label id="lab_us-gaap_GrossProfit_1252B836642FDE20E4F4F3C374001ECA_terseLabel_en-US" xlink:label="lab_us-gaap_GrossProfit_1252B836642FDE20E4F4F3C374001ECA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross profit</link:label>
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    <link:label id="lab_us-gaap_OperatingIncomeLoss_26FEE04210C544CA6395F3C37400A3CA_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_26FEE04210C544CA6395F3C37400A3CA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating income</link:label>
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    <link:label id="lab_us-gaap_OtherNonoperatingIncomeExpense_32B130A4B8A24F52765DF3C37400D098_terseLabel_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpense_32B130A4B8A24F52765DF3C37400D098" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other income, net</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax_D40896D2158412E0E785F572353C023E" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax_347AB16B60C42B863CDAF572353C2815" xlink:type="locator" />
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    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax_06172EFAA017AAD20D0DF572353C5C5B" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax_06172EFAA017AAD20D0DF572353C5C5B" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_D62B98A592DDC4EA9180F572353CC54D" xlink:type="arc" />
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    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_FD6690A8D85FBE5EC40CF572353CD8E7" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_FD6690A8D85FBE5EC40CF572353CD8E7" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax_5E07D70D875038D86C93F572353C6048_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax_5E07D70D875038D86C93F572353C6048" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Income taxes on postretirement benefit plans</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax_5E07D70D875038D86C93F572353C6048" xlink:type="locator" />
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_182155CFF886EB909A64F572353C2452_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_182155CFF886EB909A64F572353C2452" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax</link:label>
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    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_8F5C20E1A4B9097F78B7F572353C40FA_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_8F5C20E1A4B9097F78B7F572353C40FA" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Other comprehensive income, net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_8F5C20E1A4B9097F78B7F572353C40FA_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_8F5C20E1A4B9097F78B7F572353C40FA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Net of Tax</link:label>
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    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316_totalLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Comprehensive income</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1E0F265765DAD09EF1F7F572353CC316" xlink:type="arc" />
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_3A1FEC4E78BB9AE427ACF572353CEDF0_terseLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_3A1FEC4E78BB9AE427ACF572353CEDF0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Less: Comprehensive income attributable to noncontrolling interests</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_3A1FEC4E78BB9AE427ACF572353CEDF0_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_3A1FEC4E78BB9AE427ACF572353CEDF0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest</link:label>
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    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_5D150B2C5AC3115EB7430861F7B50F6E_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_5D150B2C5AC3115EB7430861F7B50F6E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating Activities:</link:label>
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