condition mean min max ZT0-3 8.636738333333334 7.325545 9.681695 ZT4-7 4.342895 4.342895 4.342895 ZT8-11 4.686405 4.686405 4.686405 ZT12-15 6.1596375 5.406485 6.912789999999999 ZT16-19 5.660885 5.660885 5.660885 ZT20-23 10.46545 10.46545 10.46545