condition mean min max ZT0-3 0.7941668333333334 0.5426675 1.176577 ZT4-7 0.411763 0.411763 0.411763 ZT8-11 1.1809675 1.1809675 1.1809675 ZT12-15 1.280489 1.130809 1.430169 ZT16-19 1.9344350000000001 1.9344350000000001 1.9344350000000001 ZT20-23 0.45568299999999995 0.45568299999999995 0.45568299999999995