condition mean min max ZT0-3 6.3717049999999995 3.901985 8.123194999999999 ZT4-7 3.2629799999999998 3.2629799999999998 3.2629799999999998 ZT8-11 10.781585 10.781585 10.781585 ZT12-15 20.58215 17.52005 23.64425 ZT16-19 15.457 15.457 15.457 ZT20-23 14.72175 14.72175 14.72175