You could also check out the Unofficial  Dynamic Range Database 
 
  
http://www.dr.loudness-war.info/ 
  
And two interesting articles on the matter, which seem to have contra-intuitive results regarding the "loudness wars" 
  
  
  
	Dynamics: evolution over the years, distributions 
 
  
  
 
  
  
  
	Dynamic Range & The Loudness War 
 
  
We all know music is getting louder. But is it less dynamic? Our ground-breaking research proves beyond any doubt that the answer is no — and that popular beliefs about the ‘loudness war’ need a radical rethink.