condition mean min max ZT0-3 20.299999999999997 20.299999999999997 20.299999999999997 ZT4-7 10.7 10.7 10.7 ZT8-11 5.8500000000000005 5.8500000000000005 5.8500000000000005 ZT12-15 14.0 14.0 14.0 ZT16-19 32.5 32.5 32.5 ZT20-23 6.25 6.25 6.25