condition mean min max ZT0-3 9.517328 9.517328 9.517328 ZT4-7 7.633353 7.633353 7.633353 ZT8-11 8.1144455 8.1144455 8.1144455 ZT12-15 7.257258 7.257258 7.257258 ZT16-19 6.9814855 6.9814855 6.9814855 ZT20-23 8.270396999999999 8.270396999999999 8.270396999999999