condition mean min max ZT0-3 4.642165 4.31387 4.97046 ZT4-7 3.620895 3.620895 3.620895 ZT8-11 3.61221 3.61221 3.61221 ZT12-15 0 0 0 ZT16-19 4.505240000000001 4.505240000000001 4.505240000000001 ZT20-23 4.35233 4.35233 4.35233