condition mean min max ZT0-3 22.4 22.4 22.4 ZT4-7 10.4 10.4 10.4 ZT8-11 15.6 15.6 15.6 ZT12-15 19.3 19.3 19.3 ZT16-19 19.85 19.85 19.85 ZT20-23 17.2 17.2 17.2