Here is a 3 1/2 year chart showing CD sales as a percentage of our album sales:
The blue line is the weekly number, while the black line is a moving 3 month average. The trend is certainly clear: CDs, especially in the past year, are declining quickly.
I'm not sure how to reconcile our sales numbers with the results of our recent survey, which showed 45% of respondents to might be interested (18% being "sounds pretty good" or "very interested") in a "CD Club"
Also note that in this survey, only 39% were possibly interested in the streaming membership (as it was explained in survey), while 71.4% were interested in the download membership, which is one reason I'm optimistic about the future.
FYI, the survey had 600 respondents, which is a good enough size to be considered valid.