Though I cannot answer what the rated capacity for Hilton was when it opened, or in 1972. I will say that seating capacity for basketball has been greater in years past. However changes in building codes, differences in seating configurations in the lower level, all of these control what is the maximum number of seats you can fill. During the Orr era, the band sat in a separate small bleacher in the corner next to the visitor's bench. I believe those bleachers are gone now. Also, I have seen games where the area directly behind the baskets at both ends is not filled with bleachers, but is a tunnel entrance covered over with an ISU banner. Anyhow, I believe I have seen in old literature a maximum seating configuration number of 15,200. But I don't know if this was ever for basketball.