stock performance graph the following graph compares the most recent five-year performance of alcoa 2019s common stock with ( 1 ) the standard & poor 2019s 500 ae index and ( 2 ) the standard & poor 2019s 500 ae materials index , a group of 27 companies categorized by standard & poor 2019s as active in the 201cmaterials 201d market sector . such information shall not be deemed to be 201cfiled . 201d five-year cumulative total return based upon an initial investment of $ 100 on december 31 , 2010 with dividends reinvested alcoa inc . s&p 500 ae index s&p 500 ae materials index dec-'10 dec-'11 dec-'12 dec-'14 dec-'15dec-'13 .
s&p 500 ae index 100 102 118 157 178 181 s&p 500 ae materials index 100 90 104 130 139 128 copyright a9 2016 standard & poor 2019s , a division of the mcgraw-hill companies inc . all rights reserved . source : research data group , inc . ( www.researchdatagroup.com/s&p.htm ) .
As of December 31, 2010 2011 2012 2013 2014 2015
AlcoaInc. $100 $57 $58 $72 $107 $68
S&P 500<sup>®</sup>Index 100 102 118 157 178 181
S&P 500<sup>®</sup>Materials Index 100 90 104 130 139 128
as of december 31, 2010 2011 2012 2013 2014 2015
alcoainc . $ 100 $ 57 $ 58 $ 72 $ 107 $ 68
s&p 500 aeindex 100 102 118 157 178 181
s&p 500 aematerials index 100 90 104 130 139 128
what was the percentual increase observed in the alcoainc . investment during 2013 and 2014?