condition mean min max ZT0-3 7.50192 6.96 8.57892 ZT4-7 7.463925 7.463925 7.463925 ZT8-11 5.9292549999999995 5.9292549999999995 5.9292549999999995 ZT12-15 9.6758625 9.49486 9.856864999999999 ZT16-19 7.504265 7.504265 7.504265 ZT20-23 9.017130000000002 9.017130000000002 9.017130000000002