I really couldn't say how many guys have been released each year, so maybe it's just your perception, but in the years covered by the old cba the cap tended to grow each year, while it's been fairly stagnant, lately.
this is from the wiki:
2013 $123 million - I believe it was originally pegged at more like 121
2012 $120.6 million
2011 $120 million
2010 Uncapped
2009 $123 million
2008 $116 million
2007 $109 million
2006 $102 million
2005 $85.5 million
2004 $80.582 million
so, you can see that, skipping the uncapped year, it's remained pretty flat the last 4 years, whereas from 2005-09 it went up 38m.
what happens is that a lot of these contracts build in some backloading to basically put off the bill collector in the expectation that the cap will rise and they will be able to better afford these deals, but when it doesn't go up they have to cut guys to stay under the cap.