condition mean min max ZT0-3 2.4991327539999997 2.409239646 2.5890258619999997 ZT4-7 7.047583298749999 5.076893724 9.018272873499999 ZT8-11 16.939828432249996 13.421745029499998 20.457911834999997 ZT12-15 24.1329450175 24.087702665000002 24.17818737 ZT16-19 14.15728147725 12.187759354499999 16.126803600000002 ZT20-23 5.23501146925 3.7437396405 6.726283298