Under the director compensation program in effect prior to November 1, 2016, directors who were not in compliance with the ownership value requirement were required to invest at least 50% of the fees they received as directors in Arconic stock until the stock ownership guideline was reached, either by deferring fees into deferred share units under the Company’s deferred fee plan for directors or purchasing shares on the open market. Deferred share units provide directors with the same economic interest as if they own Arconic common stock. Specifically, the deferred share units track the performance of our common stock and accrue dividend equivalents that are equal in value to dividends paid on our common stock. Upon a director’s retirement from the Board, the deferred share units are settled in cash at a value equivalent to the then-prevailing market value of our common stock.

Beginning November 1, 2016, directors receive a portion of their annual compensation in Arconic deferred restricted share units, which count towards meeting the stock ownership value requirement. The annual deferred restricted share unit award vests on the first anniversary of the grant date, or, if earlier, the date of the next subsequent annual meeting of shareholders following the grant date, subject to continued service through the vesting date (however, accelerated vesting provisions apply for certain termination scenarios, such as death and change in control, and pro-rata vesting provisions apply in the event of a director’s termination of service for any other reason). Settlement of the annual deferred restricted share units is deferred pursuant to the Amended and Restated Deferred Fee Plan for Directors. Also, beginning November 1, 2016, directors may elect to defer the cash portion of their annual compensation into additional Arconic deferred restricted share units (but not into deferred share units), as described under “Director Deferral Program” on page 2220. Each Arconic deferred restricted share unit is an undertaking by the Company to issue to the recipient one share of Arconic common stock upon settlement.

Accordingly, whether a director holds shares of Arconic common stock, deferred share units or deferred restricted share units, directors have the same economic interest in the performance of the Company, which further aligns directors’ interests with those of our shareholders.

The following table shows the aggregate value of each non-employeecurrent director’s holdings in Arconic common stock, deferred restricted share units, and deferred share units as of March 15, 2018,2019, based on the closing price of our common stock on the New York Stock Exchange on that date.