condition mean min max ZT0-3 2.0333267155000003 1.040625407 3.0260280240000004 ZT4-7 3.51339512275 3.309583849 3.7172063965 ZT8-11 16.977928992749998 7.3268372710000005 26.629020714499998 ZT12-15 23.237288687499998 20.41001162 26.064565755 ZT16-19 8.884377959999998 6.0253661869999995 11.743389732999999 ZT20-23 1.6190161407499999 0.9041604415 2.33387184