Differences between different years 1000 Xxc?

Going to move up from a DS 650 to a Renegade 1000 Xxc. There are new discounted 2014’s and 2015’s out there. I haven’t had much luck finding what changes were made each year; I know about the engine changes for the 2016 but other than that I’m not finding anything. Can anyone help me with info? Thanks.