condition mean min max ZT0-3 23.015966666666667 16.7825 32.5185 ZT4-7 21.065649999999998 21.065649999999998 21.065649999999998 ZT8-11 18.427999999999997 18.427999999999997 18.427999999999997 ZT12-15 15.37695 11.33075 19.42315 ZT16-19 10.49555 10.49555 10.49555 ZT20-23 16.30055 16.30055 16.30055