condition mean min max ZT0-3 22.822034 22.822034 22.822034 ZT4-7 31.537234499999997 31.537234499999997 31.537234499999997 ZT8-11 34.339 34.339 34.339 ZT12-15 33.06921 33.06921 33.06921 ZT16-19 26.9494395 26.9494395 26.9494395 ZT20-23 26.890107 26.890107 26.890107