condition mean min max ZT0-3 4.190245 4.190245 4.190245 ZT4-7 3.320365 3.320365 3.320365 ZT8-11 5.19862 5.19862 5.19862 ZT12-15 4.9281749999999995 4.9281749999999995 4.9281749999999995 ZT16-19 7.84909 7.84909 7.84909 ZT20-23 4.700375 4.700375 4.700375