condition mean min max ZT0-3 1.6430344250000002 1.327738037 1.9583308130000001 ZT4-7 1.4586701455000002 0.9528450745000001 1.9644952165 ZT8-11 2.1681224287500003 2.035581869 2.3006629885 ZT12-15 2.37240661925 2.1328113595 2.612001879 ZT16-19 2.1256916547499998 1.6849415765 2.566441733 ZT20-23 3.8352253775 3.303192812 4.367257943