condition mean min max ZT0-3 10.623275 10.3729 10.87365 ZT4-7 14.7107 14.7107 14.7107 ZT8-11 20.60215 20.60215 20.60215 ZT12-15 0 0 0 ZT16-19 15.8998 15.8998 15.8998 ZT20-23 13.98025 13.98025 13.98025