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.


generate cash without additional external financings . free cash flow should be considered in addition to , rather than as a substitute for , cash provided by operating activities . the following table reconciles cash provided by operating activities ( gaap measure ) to free cash flow ( non-gaap measure ) : millions 2014 2013 2012 . <table class='wikitable'><tr><td>1</td><td>millions</td><td>2014</td><td>2013</td><td>2012</td></tr><tr><td>2</td><td>cash provided by operating activities</td><td>$ 7385</td><td>$ 6823</td><td>$ 6161</td></tr><tr><td>3</td><td>cash used in investing activities</td><td>-4249 ( 4249 )</td><td>-3405 ( 3405 )</td><td>-3633 ( 3633 )</td></tr><tr><td>4</td><td>dividends paid</td><td>-1632 ( 1632 )</td><td>-1333 ( 1333 )</td><td>-1146 ( 1146 )</td></tr><tr><td>5</td><td>free cash flow</td><td>$ 1504</td><td>$ 2085</td><td>$ 1382</td></tr></table> 2015 outlook f0b7 safety 2013 operating a safe railroad benefits all our constituents : our employees , customers , shareholders and the communities we serve . we will continue using a multi-faceted approach to safety , utilizing technology , risk assessment , quality control , training and employee engagement , and targeted capital investments . we will continue using and expanding the deployment of total safety culture and courage to care throughout our operations , which allows us to identify and implement best practices for employee and operational safety . we will continue our efforts to increase detection of rail defects ; improve or close crossings ; and educate the public and law enforcement agencies about crossing safety through a combination of our own programs ( including risk assessment strategies ) , industry programs and local community activities across our network . f0b7 network operations 2013 in 2015 , we will continue to add resources to support growth , improve service , and replenish our surge capability . f0b7 fuel prices 2013 with the dramatic drop in fuel prices at the end of 2014 , there is even more uncertainty around the projections of fuel prices . we again could see volatile fuel prices during the year , as they are sensitive to global and u.s . domestic demand , refining capacity , geopolitical events , weather conditions and other factors . as prices fluctuate there will be a timing impact on earnings , as our fuel surcharge programs trail fluctuations in fuel price by approximately two months . lower fuel prices could have a positive impact on the economy by increasing consumer discretionary spending that potentially could increase demand for various consumer products that we transport . alternatively , lower fuel prices will likely have a negative impact on other commodities such as coal , frac sand and crude oil shipments . f0b7 capital plan 2013 in 2015 , we expect our capital plan to be approximately $ 4.3 billion , including expenditures for ptc and 218 locomotives . the capital plan may be revised if business conditions warrant or if new laws or regulations affect our ability to generate sufficient returns on these investments . ( see further discussion in this item 7 under liquidity and capital resources 2013 capital plan. ) f0b7 financial expectations 2013 we expect the overall u.s . economy to continue to improve at a moderate pace . one of the biggest uncertainties is the outlook for energy markets , which will bring both challenges and opportunities . on balance , we expect to see positive volume growth for 2015 versus the prior year . in the current environment , we expect continued margin improvement driven by continued pricing opportunities , ongoing productivity initiatives and the ability to leverage our resources as we improve the fluidity of our network. .
Question: what was free cash flow in 2014?
Answer: 1504.0
Question: what was it in 2013?

2085.0