condition mean min max ZT0-3 2.6500000000000004 2.6500000000000004 2.6500000000000004 ZT4-7 3.0 3.0 3.0 ZT8-11 5.1 5.1 5.1 ZT12-15 10.700000000000001 10.700000000000001 10.700000000000001 ZT16-19 7.5 7.5 7.5 ZT20-23 1.65 1.65 1.65