The NY Times get’s it wrong. Stats Chats takes on the numbers:
The larger category, “Musicians and Singers”, has been declining. The smaller category, “Music Directors and Composers” was going up slowly, then had a dramatic three-year, straight-line increase, then decreased a bit.
Going into the Technical Notes for the estimates (eg, 2009), we see
May 2009 estimates are based on responses from six semiannual panels collected over a 3-year period
That means the three-year increase of 5000 jobs/year is probably a one-off increase of 15,000 jobs. Either the number of “Music Directors and Composers” more than doubled in 2009, or more likely there was a change in definitions or sampling approach.
READ THE FULL STORY AT STATS CHAT:
http://www.statschat.org.nz/2015/08/22/changing-who-you-count/
The Trichordist 
Describing my StatsChat post as “the full story” is a bit much. I’m writing on one aspect of one number in the NY story. If you want to disagree with the NYT on the general issue there’s more information and discussion at the Future of Music Coalition post.