condition mean min max ZT0-3 1.1390349765 0.890312848 1.387757105 ZT4-7 2.80909396925 2.703845404 2.9143425345000002 ZT8-11 3.4695161015 2.8953920369999997 4.043640166 ZT12-15 14.1346958145 11.297354744 16.972036885 ZT16-19 18.0633834375 16.986990319999997 19.139776555 ZT20-23 19.760504165 19.516723455 20.004284875