condition mean min max ZT0-3 1.8759063333333332 1.721605 2.144754 ZT4-7 0.4063445 0.4063445 0.4063445 ZT8-11 1.70919 1.70919 1.70919 ZT12-15 1.3297107499999998 0.4640065 2.1954149999999997 ZT16-19 0.0 0.0 0.0 ZT20-23 2.52289 2.52289 2.52289