donload older version of Solidwroks. 2015

I am downloading 2020 today by the way.    

I have a customer that is on 2015 and has not upgraded.    I want to export my assembly created in a different cad package as STEP.  The customer is struggling bringing in the one STEP assembly as a Solidworks assembly.  I just want to do it for them so here I am.  I've tossed disks and our current laptops don't even have CD's LOL 

So I went to solidworks.com and logged in and noticed 2020 so Im installing that now.  But the oldest I can download to install is 2016     I need 2015     Suggestions?

Bart Brejcha

Design-engine.com 

SolidworksGeneral