condition mean min max ZT0-3 8.15 8.15 8.15 ZT4-7 5.4 5.4 5.4 ZT8-11 13.5 13.5 13.5 ZT12-15 7.15 7.15 7.15 ZT16-19 19.1 19.1 19.1 ZT20-23 34.5 34.5 34.5