Broadway did a backslide after last week’s gains, with overall box office decreasing by 3% and attendance falling 4% in week 29.Those declines were softened somewhat by newly previewing shows “Porgy and Bess” ($292,703, attendance 2,564 for two performances) and “The Road to Mecca” ($80,118, attendance 2,268 in five perfs). Subtract those ducats and butts and the Main Stem was off more than 4% in terms of dollars and nearly 6% of attendance. B.O. dropoff was especially severe at “Sister Act” ($601,705, off 23%) and the flagging one-act collection “Relatively Speaking” ($345,133, a drop of almost $400,000 from its peak in Week 23). The news was not all bad on the Rialto, though. “The Lion King” took the overall crown for the third consecutive week with a haul of $1,833,881, up 2% against last week. Audiences also flocked to “Billy Elliot” ($817,957, up 2%) in advance of its closing on Jan. 8, and “How to Succeed in Business Without Really Trying” ($1,100,832, a 6% increase) to see star Daniel Radcliffe before his upcoming departure. Plays were also hit less hard than musicals, with “Other Desert Cities” ($551,176) continuing to command a per-ticket price above $100 and “War Horse” ($988,373) galloping along at 100% attendance more than eight months after opening. The prognosis is less rosy for struggling David Henry Hwang play “Chinglish” and just-opened basketball-Greek comedy-musical “Lysistrata Jones.” “Chinglish” played to 35% of capacity at the Longacre, while “Jones” sold tickets for $25.14 on average, or $2 less than its lowest advertised price. Even taking opening-night comps into account, that’s terrible news for the newcomer. However poor the news this week, legiters should look for Broadway to bounce back nicely during the final weeks of the year as tourists swarm to Midtown Manhattan. Indeed, recently opened Harry Connick, Jr. starrer “On a Clear Day You Can See Forever” ($744,076) and “An Evening With Patti LuPone and Mandy Patinkin” ($480,422) both increased their box office by adding an eighth performance to their weekly schedules to capture the winter crowds. Overall Broadway cume tallied to $24.3 million, up nearly $400,000 against last year, when three more shows were playing.