condition mean min max ZT0-3 40.6 40.6 40.6 ZT4-7 45.7 45.7 45.7 ZT8-11 18.9 18.9 18.9 ZT12-15 34.4 34.4 34.4 ZT16-19 50.0 50.0 50.0 ZT20-23 11.7 11.7 11.7