condition mean min max ZT0-3 3.6879225 3.385445 3.9903999999999997 ZT4-7 3.067455 3.067455 3.067455 ZT8-11 6.41303 6.41303 6.41303 ZT12-15 0 0 0 ZT16-19 10.31155 10.31155 10.31155 ZT20-23 6.4675899999999995 6.4675899999999995 6.4675899999999995