After reading that I just had to make my own tally, and with Kirstein's Thirty Years and Nancy Reynolds' Repertory in Review as supplemental memory aids, I counted 62, including only works I've seen in the theater and in full, and counting Jewels as one ballet and Ballet Imperial and Tchaikovsky Piano Concerto # 2 as one ballet. My count includes a number of rarities revived by Suzanne Farrell for her company, but I have never seen Le Tombeau de Couperin, Coppelia, Harlequinade, or (in the theater) Allegro Brilliante. I'm kicking myself for passing up a chance to see Pavanne on a Saturday afternoon in New York, but then I'd seen four NYCB performances in a row and had two more to go, and New York has other charms.
Since this is the silly season on Ballet Talk, when most companies are on vacation or touring, and a ballet starved brain turns to . . . well, making lists in my case, if anyone else is feeling obsessive-compulsive, I'd love to see your own totals. I'll bet there are people here whose counts easily reach into the 80's. For a list of all Balanchine ballets -- at least according to wikipedia -- go here.