condition mean min max ZT0-3 4.21828 4.21828 4.21828 ZT4-7 3.4853949999999996 3.4853949999999996 3.4853949999999996 ZT8-11 2.87256 2.87256 2.87256 ZT12-15 2.515205 2.515205 2.515205 ZT16-19 5.418955 5.418955 5.418955 ZT20-23 3.91704 3.91704 3.91704