condition mean min max ZT0-3 3.11932759425 2.9866799065 3.251975282 ZT4-7 1.4161311954999998 1.2790306034999999 1.5532317875 ZT8-11 0.9654962545000001 0.9379217285000001 0.9930707805 ZT12-15 0.95933515025 0.947572545 0.9710977555 ZT16-19 0.7812231405000001 0.6505528975 0.9118933835 ZT20-23 2.15920060125 1.5716538624999998 2.7467473399999998