condition mean min max ZT0-3 15.424425 14.54505 16.3038 ZT4-7 18.78715 18.78715 18.78715 ZT8-11 30.905549999999998 30.905549999999998 30.905549999999998 ZT12-15 0 0 0 ZT16-19 30.636499999999998 30.636499999999998 30.636499999999998 ZT20-23 24.746850000000002 24.746850000000002 24.746850000000002