condition mean min max ZT0-3 12.242994 12.242994 12.242994 ZT4-7 10.402626 10.402626 10.402626 ZT8-11 11.512115 11.512115 11.512115 ZT12-15 11.1998675 11.1998675 11.1998675 ZT16-19 12.056178 12.056178 12.056178 ZT20-23 10.115365 10.115365 10.115365