<p>While this doesn’t answer your question, you might find it interesting. Federal financial aid as we know it today didn’t exist 50 years ago. The first major wave of federal aid was the GI Bill following WWII</p>
<p>[FinAid</a> | FinAid for Educators and FAAs | History of Student Financial Aid](<a href=“http://www.finaid.org/educators/history.phtml]FinAid”>http://www.finaid.org/educators/history.phtml)</p>
<p>More so than costs I suspect the percentages of students receiving federal aid is more dependent upon federal policies and how those policies define need. For example, it’s recognized that Reagan cut aid to students. I can personally confirm this as I was a student in need of aid at that time. If I had been a student before or after those years I would have likely ended up with far less student loan debt. </p>
<p>Google history federal financial aid percentages. You’ll find some interesting info.</p>