condition mean min max ZT0-3 32.75 32.75 32.75 ZT4-7 17.1 17.1 17.1 ZT8-11 7.0 7.0 7.0 ZT12-15 3.95 3.95 3.95 ZT16-19 10.2 10.2 10.2 ZT20-23 18.1 18.1 18.1