condition mean min max ZT0-3 0.5543776666666667 0.324953 0.6856335 ZT4-7 0.162352 0.162352 0.162352 ZT8-11 2.29027 2.29027 2.29027 ZT12-15 3.4302100000000006 2.5013 4.359120000000001 ZT16-19 1.7069450000000002 1.7069450000000002 1.7069450000000002 ZT20-23 1.883995 1.883995 1.883995