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Consolidated Statements of Equity (Unaudited) - USD ($) $ in Millions | Total | Common Stock | Additional Paid-in Capital | Retained Earnings | Accumulated Other Comprehensive Loss | Treasury Shares | Non-Controlling Interests
--- | --- | --- | --- | --- | --- | --- | ---
Balance, beginning of year at Dec. 31, 2016 |  | $ 561 | $ 842 | $ 12,388 | $ (5,093) | $ (2,506) | $ 80
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |
Change in accrued stock compensation costs |  |  | (10) |  |  |  |
Issuance of shares under stock compensation plans and employee stock purchase plans |  |  | (69) |  |  | 201 |
Cumulative effect of adoption of new revenue recognition standard and other new accounting standards |  |  |  | 0 | 0 |  |
Cumulative effect of adoption of new revenue recognition standard and other new accounting standards | Accounting Standards Update 2014-09 |  |  |  | 0 |  |  |
Net income | $ 1,085 |  |  | 1,070 |  |  | 15
Dividend equivalents declared – (per share amounts: $1.165 in 2018 and $1.06 in 2017) |  |  |  | (2) |  |  |
Dividends declared – (per share amounts: $1.165 in 2018 and $1.06 in 2017) |  |  |  | (541) |  |  |
Other comprehensive income, net of tax | 552 |  |  |  | 552 |  |
Purchase of treasury shares |  |  |  |  |  | (400) |
Distributions and other changes |  |  |  |  |  |  | (14)
Balance, end of period at Jun. 30, 2017 | 7,074 |  | 763 | 12,915 | (4,541) | (2,705) | 81
Balance, beginning of year at Dec. 31, 2017 | 7,442 | $ 561 | 784 | 13,140 | (4,043) | (3,083) | 83
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |
Change in accrued stock compensation costs |  |  | (26) |  |  |  |
Issuance of shares under stock compensation plans and employee stock purchase plans |  |  | (26) |  |  | 140 |
Cumulative effect of adoption of new revenue recognition standard and other new accounting standards |  |  |  | 0 | (14) |  |
Cumulative effect of adoption of new revenue recognition standard and other new accounting standards | Accounting Standards Update 2014-09 |  |  |  | 364 |  |  |
Net income | 1,232 |  |  | 1,221 |  |  | 11
Net income | Accounting Standards Update 2014-09 | 1,232 |  |  |  |  |  |
Dividend equivalents declared – (per share amounts: $1.165 in 2018 and $1.06 in 2017) |  |  |  | (3) |  |  |
Dividends declared – (per share amounts: $1.165 in 2018 and $1.06 in 2017) |  |  |  | (591) |  |  |
Other comprehensive income, net of tax | (208) |  |  |  | (208) |  |
Purchase of treasury shares |  |  |  |  |  | (500) |
Distributions and other changes |  |  |  |  |  |  | (13)
Balance, end of period at Jun. 30, 2018 | 7,797 |  | $ 732 | $ 14,131 | $ (4,265) | $ (3,443) | $ 81
Balance, end of period (Accounting Standards Update 2014-09) at Jun. 30, 2018 | $ 7,797 |  |  |  |  |  |

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