condition mean min max ZT0-3 13.3651 13.3651 13.3651 ZT4-7 9.49814 9.49814 9.49814 ZT8-11 10.70421 10.70421 10.70421 ZT12-15 17.9302 17.9302 17.9302 ZT16-19 23.02315 23.02315 23.02315 ZT20-23 19.0354 19.0354 19.0354