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CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands | Total | PREFERRED SHARES | COMMON SHARES, $0.01 PAR VALUE | PAID IN CAPITAL | RETAINED EARNINGS | ACCUMULATED OTHER COMPREHENSIVE (LOSS) | OPERATING PARTNERSHIP | PARTIALLY OWNED PROPERTIES
--- | --- | --- | --- | --- | --- | --- | --- | ---
Balance, beginning of year at Dec. 31, 2016 | $ 10,229,078 | $ 37,280 | $ 3,659 | $ 8,758,422 | $ 1,543,626 | $ (113,909) |  |
Balance, beginning of year at Dec. 31, 2016 | 231,906 |  |  |  |  |  | $ 221,297 | $ 10,609
COMMON SHARES, $0.01 PAR VALUE |  |  |  |  |  |  |  |
Conversion of OP Units into Common Shares |  |  | 11 | 14,706 |  |  | (14,717) |
Exercise of share options |  |  | 3 | 12,964 |  |  |  |
Employee Share Purchase Plan (ESPP) |  |  | 1 | 2,962 |  |  |  |
Restricted shares |  |  | 1 | 7,488 |  |  |  |
Share options |  |  |  | 6,384 |  |  |  |
ESPP discount |  |  |  | 586 |  |  |  |
PAID IN CAPITAL |  |  |  |  |  |  |  |
Conversion of OP Units into Common Shares |  |  | 11 | 14,706 |  |  | (14,717) |
Exercise of share options |  |  | 3 | 12,964 |  |  |  |
Employee Share Purchase Plan (ESPP) |  |  | 1 | 2,962 |  |  |  |
Share-based employee compensation expense |  |  |  |  |  |  |  |
Offering costs |  |  |  | (36) |  |  |  |
Supplemental Executive Retirement Plan (SERP) |  |  |  | (594) |  |  |  |
Change in market value of Redeemable Noncontrolling Interests – Operating Partnership | (29,551) |  |  | 29,551 |  |  |  |
Adjustment for Noncontrolling Interests ownership in Operating Partnership |  |  |  | 16,306 |  |  | (16,306) |
RETAINED EARNINGS |  |  |  |  |  |  |  |
Net income attributable to controlling interests | 478,012 |  |  |  | 478,012 |  |  |
Common Share distributions |  |  |  |  | (555,071) |  |  |
Preferred Share distributions |  |  |  |  | (2,318) |  |  |
Accumulated other comprehensive income – derivative instruments: |  |  |  |  |  |  |  |
Unrealized holding gains (losses) arising during the period | 5,216 |  |  |  |  | 5,216 |  |
Losses reclassified into earnings from other comprehensive income | (14,019) |  |  |  |  | 14,019 |  |
OPERATING PARTNERSHIP |  |  |  |  |  |  |  |
Conversion of OP Units into Common Shares |  |  | 11 | 14,706 |  |  | (14,717) |
Equity compensation associated with Noncontrolling Interests |  |  |  |  |  |  | 8,200 |
Net income | 498,297 |  |  |  |  |  |  |
Distributions to Noncontrolling Interests |  |  |  |  |  |  | (20,073) | (6,913)
Change in carrying value of Redeemable Noncontrolling Interests - Operating Partnership | (32,000) |  |  |  |  |  | 32,000 |
Adjustment for Noncontrolling Interests ownership in Operating Partnership |  |  |  | 16,306 |  |  | (16,306) |
Net income attributable to Noncontrolling Interests | 17,931 |  |  |  |  |  | 17,931 | 2,354
PARTIALLY OWNED PROPERTIES |  |  |  |  |  |  |  |
Net income | 498,297 |  |  |  |  |  |  |
Distributions to Noncontrolling Interests |  |  |  |  |  |  | (20,073) | (6,913)
Net income attributable to Noncontrolling Interests | 17,931 |  |  |  |  |  | 17,931 | 2,354
Contributions – Noncontrolling Interests – Partially Owned Properties | 125 |  |  |  |  |  |  | 125
Balance, end of period at Sep. 30, 2017 | 10,259,269 | $ 37,280 | $ 3,675 | $ 8,848,739 | $ 1,464,249 | $ (94,674) |  |
Balance, end of period at Sep. 30, 2017 | $ 234,507 |  |  |  |  |  | $ 228,332 | $ 6,175

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