condition mean min max ZT0-3 2.95 2.95 2.95 ZT4-7 8.3 8.3 8.3 ZT8-11 22.65 22.65 22.65 ZT12-15 13.8 13.8 13.8 ZT16-19 15.950000000000001 15.950000000000001 15.950000000000001 ZT20-23 13.950000000000001 13.950000000000001 13.950000000000001