condition mean min max ZT0-3 15.663284 15.663284 15.663284 ZT4-7 13.6249265 13.6249265 13.6249265 ZT8-11 27.7269195 27.7269195 27.7269195 ZT12-15 28.898496 28.898496 28.898496 ZT16-19 43.370208000000005 43.370208000000005 43.370208000000005 ZT20-23 35.5506995 35.5506995 35.5506995