condition mean min max ZT0-3 0.9140076666666667 0.48279700000000003 1.52603 ZT4-7 0.331641 0.331641 0.331641 ZT8-11 0.9866245 0.9866245 0.9866245 ZT12-15 1.14425875 0.920219 1.3682985 ZT16-19 2.32504 2.32504 2.32504 ZT20-23 1.171135 1.171135 1.171135