condition mean min max ZT0-3 176.337131 176.337131 176.337131 ZT4-7 66.8500265 66.8500265 66.8500265 ZT8-11 52.511071 52.511071 52.511071 ZT12-15 117.54095749999999 117.54095749999999 117.54095749999999 ZT16-19 59.413777499999995 59.413777499999995 59.413777499999995 ZT20-23 173.070449 173.070449 173.070449