condition mean min max ZT0-3 4.9 4.9 4.9 ZT4-7 2.0 2.0 2.0 ZT8-11 11.25 11.25 11.25 ZT12-15 37.650000000000006 37.650000000000006 37.650000000000006 ZT16-19 9.3 9.3 9.3 ZT20-23 8.15 8.15 8.15