condition mean min max ZT0-3 3.267721816 2.44513741 4.090306222 ZT4-7 5.884580355000001 4.305459261 7.463701449 ZT8-11 9.640476572833332 9.395991886 9.884961259666667 ZT12-15 8.162812723833333 7.5879210210000005 8.737704426666667 ZT16-19 8.490124593166666 8.410269058 8.569980128333333 ZT20-23 4.686400128 4.0546981073333335 5.318102148666666