condition mean min max ZT0-3 8.185946666666666 1.43051 12.421050000000001 ZT4-7 2.346755 2.346755 2.346755 ZT8-11 2.65931 2.65931 2.65931 ZT12-15 5.0433924999999995 3.8791349999999998 6.20765 ZT16-19 7.282114999999999 7.282114999999999 7.282114999999999 ZT20-23 13.35135 13.35135 13.35135