condition mean min max ZT0-3 6.05 6.05 6.05 ZT4-7 8.1 8.1 8.1 ZT8-11 14.950000000000001 14.950000000000001 14.950000000000001 ZT12-15 16.65 16.65 16.65 ZT16-19 5.1 5.1 5.1 ZT20-23 7.8999999999999995 7.8999999999999995 7.8999999999999995