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Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
CASH FLOWS PROVIDED BY OPERATING ACTIVITIES: |  |  |
Net income | $ 69,500 | $ 61,071 | $ 55,027
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation | 102,893 | 95,137 | 88,585
Tires in service amortization | 6,575 | 6,861 | 6,982
Deferred income taxes | (924) | 16,045 | 5,351
Share-based payment arrangement compensation expense | 1,851 | 1,817 | 3,323
Equity in loss (earnings) from affiliate | 0 | 155 | (493)
Distribution from affiliate | 0 | 0 | 227
Adoption of accounting standard | 0 | 0 | 485
Changes in other current operating items: |  |  |
Receivables | 12,726 | (13,638) | (8,131)
Prepaid expenses and other | (4,593) | (4,105) | (3,515)
Accounts payable | 883 | 5,259 | 1,800
Insurance and claims accruals | 7,866 | 3,626 | 1,926
Accrued and other current liabilities | 3,272 | (7,088) | 9,881
Net cash provided by operating activities | 189,598 | 156,460 | 154,204
CASH FLOWS USED FOR INVESTING ACTIVITIES: |  |  |
Disposition of investment in affiliate | 0 | 1,168 | 0
Other | (39) | (25) | (15)
Net cash used for investing activities | (106,325) | (140,509) | (104,851)
CASH FLOWS USED FOR FINANCING ACTIVITIES: |  |  |
Dividends on common stock | (52,366) | (42,089) | (5,459)
Issuance of common stock from share-based payment arrangement exercises | 4,793 | 1,620 | 938
Repurchase and retirement of common stock | (597) | 0 | (3,756)
Employee taxes paid in exchange for shares withheld | (437) | (784) | (104)
Net cash used for financing activities | (48,607) | (41,253) | (8,381)
NET CHANGE IN CASH AND CASH EQUIVALENTS | 34,666 | (25,302) | 40,972
CASH AND CASH EQUIVALENTS: |  |  |
Beginning of year | 31,461 | 56,763 | 15,791
End of year | 66,127 | 31,461 | 56,763
SUPPLEMENTAL NON-CASH DISCLOSURE: |  |  |
Change in property and equipment not yet paid | 3,230 | 249 | (3,604)
Operating lease assets and liabilities acquired | 88 | 1,668 | 0
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION: |  |  |
Income taxes | 17,980 | 4,953 | 9,526
Interest | 0 | 52 | 50
Revenue Equipment [Member] |  |  |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Gain on disposition of property, plant and equipment | (8,733) | (8,680) | (7,244)
CASH FLOWS USED FOR INVESTING ACTIVITIES: |  |  |
Property, plant and equipment additions | (166,395) | (184,680) | (161,160)
Proceeds from property, plant and equipment dispositions | 64,185 | 47,745 | 63,681
Facility [Member] |  |  |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Gain on disposition of property, plant and equipment | (1,718) | 0 | 0
Buildings And Land Office Equipment And Other [Member] |  |  |
CASH FLOWS USED FOR INVESTING ACTIVITIES: |  |  |
Property, plant and equipment additions | (6,657) | (4,723) | (7,362)
Proceeds from property, plant and equipment dispositions | $ 2,581 | $ 6 | $ 5

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