condition mean min max ZT0-3 13.443233333333334 11.181550000000001 15.4211 ZT4-7 9.34854 9.34854 9.34854 ZT8-11 10.713149999999999 10.713149999999999 10.713149999999999 ZT12-15 19.27425 18.764699999999998 19.7838 ZT16-19 15.808699999999998 15.808699999999998 15.808699999999998 ZT20-23 16.83145 16.83145 16.83145