I'm confused with the CSS and FAFSA?

Let me get this straight. With the CSS do I Just need the 2014 tax return with a demographic of my mothers 2015 earnings. Or do I need both. And with The FAFSA do I need both ?

You should be filing the 2016-2017 FAFSA and Profile forms using 2015 tax year information.

I believe the Profile also asks for the previous year income and an estimate of 2016.