condition mean min max ZT0-3 10.226215 10.226215 10.226215 ZT4-7 8.68287 8.68287 8.68287 ZT8-11 10.05642 10.05642 10.05642 ZT12-15 5.29617 5.29617 5.29617 ZT16-19 8.41417 8.41417 8.41417 ZT20-23 7.49165 7.49165 7.49165