condition mean min max ZT0-3 4.1 4.1 4.1 ZT4-7 0.5 0.5 0.5 ZT8-11 20.25 20.25 20.25 ZT12-15 32.65 32.65 32.65 ZT16-19 9.0 9.0 9.0 ZT20-23 26.450000000000003 26.450000000000003 26.450000000000003