condition mean min max ZT0-3 30.215558 30.215558 30.215558 ZT4-7 30.906872 30.906872 30.906872 ZT8-11 21.2632665 21.2632665 21.2632665 ZT12-15 25.698634 25.698634 25.698634 ZT16-19 29.718634 29.718634 29.718634 ZT20-23 22.830012 22.830012 22.830012