Financial report context:
the goldman sachs group , inc . and subsidiaries notes to consolidated financial statements in connection with the firm 2019s prime brokerage and clearing businesses , the firm agrees to clear and settle on behalf of its clients the transactions entered into by them with other brokerage firms . the firm 2019s obligations in respect of such transactions are secured by the assets in the client 2019s account as well as any proceeds received from the transactions cleared and settled by the firm on behalf of the client . in connection with joint venture investments , the firm may issue loan guarantees under which it may be liable in the event of fraud , misappropriation , environmental liabilities and certain other matters involving the borrower . the firm is unable to develop an estimate of the maximum payout under these guarantees and indemnifications . however , management believes that it is unlikely the firm will have to make any material payments under these arrangements , and no material liabilities related to these guarantees and indemnifications have been recognized in the consolidated statements of financial condition as of december 2016 and december 2015 . other representations , warranties and indemnifications . the firm provides representations and warranties to counterparties in connection with a variety of commercial transactions and occasionally indemnifies them against potential losses caused by the breach of those representations and warranties . the firm may also provide indemnifications protecting against changes in or adverse application of certain u.s . tax laws in connection with ordinary-course transactions such as securities issuances , borrowings or derivatives . in addition , the firm may provide indemnifications to some counterparties to protect them in the event additional taxes are owed or payments are withheld , due either to a change in or an adverse application of certain non-u.s . tax laws . these indemnifications generally are standard contractual terms and are entered into in the ordinary course of business . generally , there are no stated or notional amounts included in these indemnifications , and the contingencies triggering the obligation to indemnify are not expected to occur . the firm is unable to develop an estimate of the maximum payout under these guarantees and indemnifications . however , management believes that it is unlikely the firm will have to make any material payments under these arrangements , and no material liabilities related to these arrangements have been recognized in the consolidated statements of financial condition as of december 2016 and december 2015 . guarantees of subsidiaries . group inc . fully and unconditionally guarantees the securities issued by gs finance corp. , a wholly-owned finance subsidiary of the group inc . has guaranteed the payment obligations of goldman , sachs & co . ( gs&co. ) and gs bank usa , subject to certain exceptions . in addition , group inc . guarantees many of the obligations of its other consolidated subsidiaries on a transaction-by- transaction basis , as negotiated with counterparties . group inc . is unable to develop an estimate of the maximum payout under its subsidiary guarantees ; however , because these guaranteed obligations are also obligations of consolidated subsidiaries , group inc . 2019s liabilities as guarantor are not separately disclosed . note 19 . shareholders 2019 equity common equity dividends declared per common share were $ 2.60 in 2016 , $ 2.55 in 2015 and $ 2.25 in 2014 . on january 17 , 2017 , group inc . declared a dividend of $ 0.65 per common share to be paid on march 30 , 2017 to common shareholders of record on march 2 , 2017 . the firm 2019s share repurchase program is intended to help maintain the appropriate level of common equity . the share repurchase program is effected primarily through regular open-market purchases ( which may include repurchase plans designed to comply with rule 10b5-1 ) , the amounts and timing of which are determined primarily by the firm 2019s current and projected capital position , but which may also be influenced by general market conditions and the prevailing price and trading volumes of the firm 2019s common stock . prior to repurchasing common stock , the firm must receive confirmation that the federal reserve board does not object to such capital actions . the table below presents the amount of common stock repurchased by the firm under the share repurchase program. .

Financial table:
in millions except per share amounts: common share repurchases; year ended december 2016: 36.6; year ended december 2015: 22.1; year ended december 2014: 31.8
in millions except per share amounts: average cost per share; year ended december 2016: $ 165.88; year ended december 2015: $ 189.41; year ended december 2014: $ 171.79
in millions except per share amounts: total cost of common share repurchases; year ended december 2016: $ 6069; year ended december 2015: $ 4195; year ended december 2014: $ 5469

Additional report context:
172 goldman sachs 2016 form 10-k .

Question: what was the difference in millions between the total cost of common shares repurchases from 2015 to 2016?
Answer: -1274