NASHVILLE (AP) - Even when they were little, The Band Perry knew what the "sophomore slump" was. Singer Kimberley Perry says they were "music business nerds" and would read every thing they could about the business they wanted to be a part of. Reid Perry says "sophomore slump" is "like the title of a horror movie for us." They need not have worried. The Band Perry's second album, "Pioneer," sold 129,000 copies this week.