condition mean min max ZT0-3 20.237141 17.03715627 23.43712573 ZT4-7 10.906121114000001 10.337871098 11.474371130000002 ZT8-11 7.530102388 5.187290185 9.872914591 ZT12-15 2.3889467545 2.2206881110000003 2.557205398 ZT16-19 5.2244946612500005 4.1681431235 6.280846199 ZT20-23 13.03829228 11.5591808 14.51740376