condition mean min max ZT0-3 5.65 5.65 5.65 ZT4-7 2.0 2.0 2.0 ZT8-11 9.45 9.45 9.45 ZT12-15 20.55 20.55 20.55 ZT16-19 3.95 3.95 3.95 ZT20-23 5.1 5.1 5.1