condition mean min max ZT0-3 1043.312316 1043.312316 1043.312316 ZT4-7 1291.0801325 1291.0801325 1291.0801325 ZT8-11 1227.5535625 1227.5535625 1227.5535625 ZT12-15 1158.2897495 1158.2897495 1158.2897495 ZT16-19 834.7657829999999 834.7657829999999 834.7657829999999 ZT20-23 498.773243 498.773243 498.773243