condition mean min max ZT0-3 33.1 33.1 33.1 ZT4-7 32.7 32.7 32.7 ZT8-11 9.2 9.2 9.2 ZT12-15 13.95 13.95 13.95 ZT16-19 19.3 19.3 19.3 ZT20-23 10.95 10.95 10.95