item 7 . management 2019s discussion and analysis of financial condition and results of operations our management 2019s discussion and analysis of financial condition and results of operations ( md&a ) is provided in addition to the accompanying consolidated financial statements and notes to assist readers in understanding our results of operations , financial condition , and cash flows . md&a is organized as follows : 2022 overview . discussion of our business and overall analysis of financial and other highlights affecting the company in order to provide context for the remainder of md&a . 2022 critical accounting estimates . accounting estimates that we believe are most important to understanding the assumptions and judgments incorporated in our reported financial results and forecasts . 2022 results of operations . an analysis of our financial results comparing 2013 to 2012 and comparing 2012 to 2022 liquidity and capital resources . an analysis of changes in our balance sheets and cash flows , and discussion of our financial condition and potential sources of liquidity . 2022 fair value of financial instruments . discussion of the methodologies used in the valuation of our financial instruments . 2022 contractual obligations and off-balance-sheet arrangements . overview of contractual obligations , contingent liabilities , commitments , and off-balance-sheet arrangements outstanding as of december 28 , 2013 , including expected payment schedule . the various sections of this md&a contain a number of forward-looking statements that involve a number of risks and uncertainties . words such as 201canticipates , 201d 201cexpects , 201d 201cintends , 201d 201cplans , 201d 201cbelieves , 201d 201cseeks , 201d 201cestimates , 201d 201ccontinues , 201d 201cmay , 201d 201cwill , 201d 201cshould , 201d and variations of such words and similar expressions are intended to identify such forward-looking statements . in addition , any statements that refer to projections of our future financial performance , our anticipated growth and trends in our businesses , uncertain events or assumptions , and other characterizations of future events or circumstances are forward-looking statements . such statements are based on our current expectations and could be affected by the uncertainties and risk factors described throughout this filing and particularly in 201crisk factors 201d in part i , item 1a of this form 10-k . our actual results may differ materially , and these forward-looking statements do not reflect the potential impact of any divestitures , mergers , acquisitions , or other business combinations that had not been completed as of february 14 , 2014 . overview our results of operations for each period were as follows: .

Table: ( dollars in millions except per share amounts ) three months ended dec . 282013 three months ended sept . 282013 three months ended change three months ended dec . 282013 three months ended dec . 292012 change net revenue $ 13834 $ 13483 $ 351 $ 52708 $ 53341 $ -633 ( 633 ) gross margin $ 8571 $ 8414 $ 157 $ 31521 $ 33151 $ -1630 ( 1630 ) gross margin percentage 62.0% ( 62.0 % ) 62.4% ( 62.4 % ) ( 0.4 ) % (  % ) 59.8% ( 59.8 % ) 62.1% ( 62.1 % ) ( 2.3 ) % (  % ) operating income $ 3549 $ 3504 $ 45 $ 12291 $ 14638 $ -2347 ( 2347 ) net income $ 2625 $ 2950 $ -325 ( 325 ) $ 9620 $ 11005 $ -1385 ( 1385 ) diluted earnings per common share $ 0.51 $ 0.58 $ -0.07 ( 0.07 ) $ 1.89 $ 2.13 $ -0.24 ( 0.24 )

revenue for 2013 was down 1% ( 1 % ) from 2012 . pccg experienced lower platform unit sales in the first half of the year , but saw offsetting growth in the back half as the pc market began to show signs of stabilization . dcg continued to benefit from the build out of internet cloud computing and the strength of our product portfolio resulting in increased platform volumes for dcg for the year . higher factory start-up costs for our next-generation 14nm process technology led to a decrease in gross margin compared to 2012 . in response to the current business environment and to better align resources , management approved several restructuring actions including targeted workforce reductions as well as the exit of certain businesses and facilities . these actions resulted in restructuring and asset impairment charges of $ 240 million for 2013 . table of contents .

Question: what was the percentage change in diluted earnings per common share december 29 2012 and december 28 2013?
Answer: -11%
Calculation: divide(subtract(1.89, 2.13), 2.13)