condition mean min max ZT0-3 10.890103333333332 6.94561 13.02695 ZT4-7 6.107385000000001 6.107385000000001 6.107385000000001 ZT8-11 4.090495 4.090495 4.090495 ZT12-15 7.432835 7.134235 7.731434999999999 ZT16-19 11.39555 11.39555 11.39555 ZT20-23 14.37605 14.37605 14.37605