condition mean min max ZT0-3 4.329165 4.07049 4.58784 ZT4-7 4.093255 4.093255 4.093255 ZT8-11 3.6680849999999996 3.6680849999999996 3.6680849999999996 ZT12-15 0 0 0 ZT16-19 5.41347 5.41347 5.41347 ZT20-23 5.404105 5.404105 5.404105