condition mean min max ZT0-3 25.450000000000003 25.450000000000003 25.450000000000003 ZT4-7 53.6 53.6 53.6 ZT8-11 15.05 15.05 15.05 ZT12-15 55.3 55.3 55.3 ZT16-19 30.5 30.5 30.5 ZT20-23 12.85 12.85 12.85