While some of that is happening, I think with many folks here you do the math with the following factors: life expectancy with good hearing, amount of time for listening, square footage of storage space available, and current inventory of cds. If you own several thousand CDs (heck, even just 1000) and you're over 40, there's a chunk of music that may never get played again. Might as well start culling the collection (to free up space & cash to buy more! )
I think your numbers are way off Q. And with retirement, one has more time to listen to music.
I play an average of in the region of 3,000 different albums in a year. That, naturally, allows for newies to be played quite a lot, and the total is sensitive to the number of new albums I buy. But there are only 36 albums that I haven't listened to for ten years or more, most often because they're a bit fucked, y'know.
MG