condition mean min max ZT0-3 1.7783650000000002 1.49588 2.0608500000000003 ZT4-7 0.6405955 0.6405955 0.6405955 ZT8-11 0.413933 0.413933 0.413933 ZT12-15 0 0 0 ZT16-19 1.0367119999999999 1.0367119999999999 1.0367119999999999 ZT20-23 1.62942 1.62942 1.62942