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Pay vs Performance Disclosure - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Pay vs Performance Disclosure |  |  |  |  |
Pay vs Performance Disclosure, Table |  | Pay Versus Performance Table The following table sets forth information concerning the compensation of our NEOs for each of the fiscal years in the four-year period ended December 31, 2023, and our financial performance for each such fiscal year:
Year | Summary Compensation Table Total for PEO ($) | Compensation Actually Paid to PEO ($)(1) | Average Summary Compensation Table Total for Non-PEO NEOs ($) | Average Compensation Actually Paid to Non-PEO NEOs ($)(1) | Value of Initial Fixed $100 Investment Based on: | Net Income ($) | Return on Equity(3)
Total Shareholder Return ($) | Peer Group Total Shareholder Return ($)(2)
2023 | 20,150,620 | 24,757,884 | 7,028,000 | 7,810,003 | 124.27 | 150.97 | 1,391,400,000 | 40.5%
2022 | 20,679,168 | 24,500,414 | 7,771,045 | 8,841,167 | 113.42 | 127.21 | 1,316,500,000 | 40.4%
2021 | 19,981,715 | 28,011,719 | 7,294,539 | 8,650,622 | 98.01 | 139.44 | 1,407,800,000 | 44.3%
2020 | 11,147,799 | 14,522,809 | 2,569,825 | 3,475,738 | 80.42 | 91.93 | 945,400,000 | 31.8%
​(1) Amounts represent compensation actually paid to our PEO and the average compensation actually paid to our remaining NEOs for the relevant fiscal year, as determined under SEC rules (and described below), which includes the individuals indicated in the table below for each fiscal year: ​(2) Represents the cumulative TSR (the “Peer Group TSR”) for the following peer companies for each fiscal year: The Interpublic Group of Companies, Inc., WPP plc and Publicis Groupe SA. ​(3) Return on Equity is a non-GAAP measure and is calculated by dividing our total net income for the applicable fiscal year, as reported in our consolidated financial statements contained in our Annual Report on Form 10-K for the applicable fiscal year, by our average shareholders’ equity for such fiscal year. Average shareholders’ equity for a fiscal year is determined by averaging our fiscal year-end shareholders’ equity and our prior fiscal year-end shareholders’ equity, as reported in our consolidated financial statements contained in our Annual Report on Form 10-K for the applicable fiscal year. |  |  |
Company Selected Measure Name |  | TSR |  |  |
Named Executive Officers, Footnote |  |
| Year | PEO | Non-PEO NEOs |
| 2023 | John Wren | Daryl Simm, Philip Angelastro, Jonathan Nelson and Louis Januzzi |
2022 | John Wren | Daryl Simm, Philip Angelastro, Jonathan Nelson and Michael O’Brien
2021 | John Wren | Daryl Simm, Philip Angelastro, Jonathan Nelson and Michael O’Brien
2020 | John Wren | Philip Angelastro, Jonathan Nelson, Michael O’Brien and Rochelle Tarlowe
Peer Group Issuers, Footnote |  | Represents the cumulative TSR (the “Peer Group TSR”) for the following peer companies for each fiscal year: The Interpublic Group of Companies, Inc., WPP plc and Publicis Groupe SA. |  |  |
PEO Total Compensation Amount |  | $ 20,150,620 | $ 20,679,168 | $ 19,981,715 | $ 11,147,799
PEO Actually Paid Compensation Amount | [1] | 24,757,884 | 24,500,414 | 28,011,719 | 14,522,809
Non-PEO NEO Average Total Compensation Amount |  | 7,028,000 | 7,771,045 | 7,294,539 | 2,569,825
Non-PEO NEO Average Compensation Actually Paid Amount | [1] | $ 7,810,003 | 8,841,167 | 8,650,622 | 3,475,738
Adjustment to Non-PEO NEO Compensation Footnote |  |
Adjustments | 2023
PEO | Average Non-PEO NEOs
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | $ (6,999,965) | $ (3,100,013)
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | $ 6,569,396 | $ 2,909,331
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | $ 1,015,140 | $ 371,537
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | $ 1,616,060 | $ 219,695
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | $ 2,406,633 | $ 381,453
TOTAL ADJUSTMENTS | $ 4,607,264 | $ 782,003
Compensation Actually Paid vs. Total Shareholder Return |  |  |  |  |
Compensation Actually Paid vs. Net Income |  |  |  |  |
Compensation Actually Paid vs. Company Selected Measure |  |  |  |  |
Tabular List, Table |  | Pay Versus Performance Tabular List We believe the following performance measures represent the most important financial performance measures used by us to determine compensation actually paid to our NEOs for the fiscal year ended December 31, 2023: ■ Return on Equity; ■ Organic Growth; ■ Adjusted Operating Margin; ■ Adjusted Diluted EPS Growth; and ■ Adjusted EBITA Margin. For additional details regarding our most important financial performance measures, please see the section titled “Performance-Based Compensation Awards” in our Compensation Discussion and Analysis elsewhere in this Proxy Statement. |  |  |
Total Shareholder Return Amount |  | $ 124.27 | 113.42 | 98.01 | 80.42
Peer Group Total Shareholder Return Amount | [2] | 150.97 | 127.21 | 139.44 | 91.93
Net Income (Loss) |  | $ 1,391,400,000 | $ 1,316,500,000 | $ 1,407,800,000 | $ 945,400,000
PEO Name |  | John Wren | John Wren | John Wren | John Wren
Return on equity percentage | [3] | 40.50% | 40.40% | 44.30% | 31.80%
Measure:: 1 |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Name |  | Return on Equity |  |  |
Measure:: 2 |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Name |  | Organic Growth |  |  |
Measure:: 3 |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Name |  | Adjusted Operating Margin |  |  |
Measure:: 4 |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Name |  | Adjusted Diluted EPS Growth |  |  |
Measure:: 5 |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Name |  | Adjusted EBITA Margin |  |  |
PEO [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | $ 4,607,264 |  |  |
PEO [Member] | Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | (6,999,965) |  |  |
PEO [Member] | Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 6,569,396 |  |  |
PEO [Member] | Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 1,015,140 |  |  |
PEO [Member] | Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 1,616,060 |  |  |
PEO [Member] | Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 2,406,633 |  |  |
Average Non PEO NEOs [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 782,003 |  |  |
Average Non PEO NEOs [Member] | Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | (3,100,013) |  |  |
Average Non PEO NEOs [Member] | Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 2,909,331 |  |  |
Average Non PEO NEOs [Member] | Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 371,537 |  |  |
Average Non PEO NEOs [Member] | Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | 219,695 |  |  |
Average Non PEO NEOs [Member] | Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date [Member] |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |
Adjustment to Compensation, Amount |  | $ 381,453 |  |  |
[1] | Amounts represent compensation actually paid to our PEO and the average compensation actually paid to our remaining NEOs for the relevant fiscal year, as determined under SEC rules (and described below), which includes the individuals indicated in the table below for each fiscal year:
[2] | Represents the cumulative TSR (the “Peer Group TSR”) for the following peer companies for each fiscal year: The Interpublic Group of Companies, Inc., WPP plc and Publicis Groupe SA.
[3] | Return on Equity is a non-GAAP measure and is calculated by dividing our total net income for the applicable fiscal year, as reported in our consolidated financial statements contained in our Annual Report on Form 10-K for the applicable fiscal year, by our average shareholders’ equity for such fiscal year. Average shareholders’ equity for a fiscal year is determined by averaging our fiscal year-end shareholders’ equity and our prior fiscal year-end shareholders’ equity, as reported in our consolidated financial statements contained in our Annual Report on Form 10-K for the applicable fiscal year.

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