condition mean min max ZT0-3 8.208867995 3.13909524 13.27864075 ZT4-7 2.5579568185 1.455094473 3.6608191640000003 ZT8-11 5.464427268750001 4.5762475875 6.35260695 ZT12-15 4.922531147500001 4.4387350635 5.406327231500001 ZT16-19 2.70151790325 2.5618563065 2.8411795 ZT20-23 3.833574267 3.5300993304999997 4.1370492035