condition mean min max ZT0-3 1.41394617575 1.3494668505 1.478425501 ZT4-7 2.73263345725 2.2003419775 3.264924937 ZT8-11 5.944288202499999 5.065662190499999 6.8229142145 ZT12-15 9.51636533 8.080523595999999 10.952207064 ZT16-19 13.06993879675 11.1217225635 15.018155029999999 ZT20-23 18.7545946875 17.406578194999998 20.10261118