condition mean min max ZT0-3 29.86995 28.82715 30.91275 ZT4-7 24.11295 24.11295 24.11295 ZT8-11 15.48855 15.48855 15.48855 ZT12-15 0 0 0 ZT16-19 18.8437 18.8437 18.8437 ZT20-23 24.33285 24.33285 24.33285