condition mean min max ZT0-3 46.6 46.6 46.6 ZT4-7 53.5 53.5 53.5 ZT8-11 30.05 30.05 30.05 ZT12-15 9.45 9.45 9.45 ZT16-19 17.9 17.9 17.9 ZT20-23 39.2 39.2 39.2