condition mean min max ZT0-3 1.5059639475 1.449810813 1.5621170819999999 ZT4-7 3.3823660915 2.735912413 4.02881977 ZT8-11 6.50267636 5.8404449735 7.164907746499999 ZT12-15 10.131236337 9.280976684 10.981495989999999 ZT16-19 10.792439109 9.412813197999998 12.17206502 ZT20-23 12.490342482500001 12.47476951 12.505915455