condition mean min max ZT0-3 1.4484750447499999 1.208135459 1.6888146305 ZT4-7 1.6103733315000002 1.5078466760000002 1.7128999870000001 ZT8-11 1.6082147199999999 1.5333816875 1.6830477524999998 ZT12-15 3.40789913275 2.1568142245 4.658984041 ZT16-19 4.56368376425 4.057599555 5.0697679735 ZT20-23 6.2651361715 6.027548942999999 6.5027234