condition mean min max ZT0-3 2.6094546032499997 2.5059617175 2.712947489 ZT4-7 2.0078679965 1.6148217885 2.4009142045000003 ZT8-11 2.56427300975 2.4253663845 2.703179635 ZT12-15 4.142272108999999 3.1334407845 5.151103433499999 ZT16-19 5.831179263499999 4.4927608415 7.169597685499999 ZT20-23 13.17898632 11.13398673 15.22398591