condition mean min max ZT0-3 1.1086901666666666 0.722753 1.77081 ZT4-7 1.2128299999999999 1.2128299999999999 1.2128299999999999 ZT8-11 1.9367050000000001 1.9367050000000001 1.9367050000000001 ZT12-15 2.5501424999999998 2.318675 2.78161 ZT16-19 2.291525 2.291525 2.291525 ZT20-23 2.12877 2.12877 2.12877