condition mean min max ZT0-3 3.6792063555 3.38804883 3.9703638810000004 ZT4-7 3.8196228015 3.406546229 4.232699374 ZT8-11 3.503169453 3.2240390095 3.7822998964999996 ZT12-15 3.2121627017499996 2.2851031725 4.139222231 ZT16-19 3.5509349142500004 2.7590245915000002 4.342845237000001 ZT20-23 7.16662211725 6.8312414035 7.5020028309999995