. . . it's a lot! 261 times in the 2012-13 season.
Take a look at Norman Lebrecht's blog post.
I prepared the Swedish Radio Choir for a Brahms Requiem with him and the Rotterdam Philharmonic (his swan song as that orchestra's music director, which is on DVD, but I wasn't able to be at the rehearsal/recording with him.
Here's Wie lieblich.