condition mean min max ZT0-3 8.5325525 7.823865 9.24124 ZT4-7 5.8007 5.8007 5.8007 ZT8-11 5.79208 5.79208 5.79208 ZT12-15 0 0 0 ZT16-19 10.61175 10.61175 10.61175 ZT20-23 8.95614 8.95614 8.95614