condition mean min max ZT0-3 3.6500000000000004 3.6500000000000004 3.6500000000000004 ZT4-7 3.5 3.5 3.5 ZT8-11 6.25 6.25 6.25 ZT12-15 7.95 7.95 7.95 ZT16-19 8.3 8.3 8.3 ZT20-23 18.900000000000002 18.900000000000002 18.900000000000002