The publicity garnered by “The Phantom of the Opera” over its 10,000th performance a couple of weeks ago may be paying off: The 24-year-old Broadway stalwart saw sales spike in Week 39 (Feb. 20-26), standing out in a frame that proved relatively healthy for most of the Rialto.“Phantom” ($985,906) was up more than $180,000, or 23%. Adding to the pot were robust returns for “Death of a Salesman” ($692,172 for seven perfs); the revival broke a B.O. record at the Barrymore Theater in its second week of previews. The production turns consumer heads with a well-known title and a cast that includes Philip Seymour Hoffman and Andrew Garfield. “How to Succeed in Business Without Really Trying” ($823,986) saw a notable rise, with the musical revival probably starting to benefit from the incipient cycle of academic breaks that can bring out the youthful fans of Nick Jonas, the production’s most recent topliner. “Stick Fly” ($449,964), meanwhile, got a push from last-minute biz in its final frame on the boards, climbing 23%. Overall, sales were up slightly, climbing about $245,000 to $20.3 million for the 26 shows on the boards. Attendance was up around 7,000 to 217,156. The 17 musicals grossed $16,225,943 for 79.9% of the Broadway total, with attendance of 167,119 and an average paid admission of $97.09. The nine plays grossed $4,089,267 for 20.1% of the Broadway total, with attendance of 50,037 and an average paid admission of $81.72.