condition mean min max ZT0-3 3.25 3.25 3.25 ZT4-7 16.0 16.0 16.0 ZT8-11 16.25 16.25 16.25 ZT12-15 2.25 2.25 2.25 ZT16-19 11.25 11.25 11.25 ZT20-23 2.0 2.0 2.0