Back in 2013 Google said they would work on giving us up to one-year worth of data (up from 90-days) in the Google Search Console (known then as Google Webmaster Tools). Well, that never happened and we thought maybe it would happen in 2015 but that seems unlikely now. Michael Fink from Google's Search Console team had it on his poll list, so I doubt it is coming in 2015.
A webmaster named Ahmed Khalifa asked this question on Twitter and Zineb from Google responded on Twitter saying it is in the plans but they have no timeline yet.
Here is the question:
@methode hey Gary, are there still plans to increase the Search Analytics data on GSC from 90 days to 1 year?
— Ahmed Khalifa (@ahmed_khalifa) November 2, 2015
Here is Zineb's response:
@methode @ahmed_khalifa plans? Yes. Timeline? Not really :)
— Zineb Ait (@Missiz_Z) November 4, 2015
So hopefully in 2016?
Forum discussion at Twitter.