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 . 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  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 ) .
Question: what was the investment on the alcoainc . in 2014?
Steps: Ask for number 107
Answer: 107.0
Question: and what was it in 2013?

Read the following texts and table with financial data from an S&P 500 earnings report carefully.Based on the question-answer history (if provided), answer the last question. The answer may require mathematical calculation based on the data provided.
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 . 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  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 ) .
Question: what was the investment on the alcoainc . in 2014?
Steps: Ask for number 107
Answer: 107.0
Question: and what was it in 2013?
