condition mean min max ZT0-3 1.6913200000000002 1.6913200000000002 1.6913200000000002 ZT4-7 1.6651150000000001 1.6651150000000001 1.6651150000000001 ZT8-11 1.1812555 1.1812555 1.1812555 ZT12-15 1.25704 1.25704 1.25704 ZT16-19 2.5472200000000003 2.5472200000000003 2.5472200000000003 ZT20-23 3.1417200000000003 3.1417200000000003 3.1417200000000003