condition mean min max ZT0-3 1.80716 1.374355 2.13154 ZT4-7 1.028707 1.028707 1.028707 ZT8-11 1.4348049999999999 1.4348049999999999 1.4348049999999999 ZT12-15 2.2051775 2.043075 2.36728 ZT16-19 2.162365 2.162365 2.162365 ZT20-23 2.350775 2.350775 2.350775