condition mean min max ZT0-3 23.36179653 21.68449151 25.03910155 ZT4-7 15.351834689999999 14.778145039999998 15.925524339999999 ZT8-11 11.0395264745 10.070287453999999 12.008765495 ZT12-15 7.87715681725 6.9551181500000006 8.7991954845 ZT16-19 6.73948762 6.3939110625 7.0850641775 ZT20-23 3.63549873275 2.3661358075 4.904861658