condition mean min max ZT0-3 15.69887 5.468909999999999 22.17765 ZT4-7 7.570365 7.570365 7.570365 ZT8-11 4.9704 4.9704 4.9704 ZT12-15 6.207784999999999 4.818735 7.596835 ZT16-19 9.86876 9.86876 9.86876 ZT20-23 15.7086 15.7086 15.7086