condition mean min max ZT0-3 8.867695 8.867695 8.867695 ZT4-7 11.737659 11.737659 11.737659 ZT8-11 11.9841165 11.9841165 11.9841165 ZT12-15 10.091662 10.091662 10.091662 ZT16-19 11.1642025 11.1642025 11.1642025 ZT20-23 11.9355015 11.9355015 11.9355015