condition mean min max ZT0-3 1.0174676666666667 0.291747 1.590218 ZT4-7 0.1402996 0.1402996 0.1402996 ZT8-11 0.3228855 0.3228855 0.3228855 ZT12-15 0.6092899999999999 0.36889099999999997 0.8496889999999999 ZT16-19 1.19309 1.19309 1.19309 ZT20-23 1.3808850000000001 1.3808850000000001 1.3808850000000001