condition mean min max ZT0-3 0.02477295 0.0 0.0495459 ZT4-7 0.0505515 0.0505515 0.0505515 ZT8-11 0.0 0.0 0.0 ZT12-15 0 0 0 ZT16-19 0.0489184 0.0489184 0.0489184 ZT20-23 0.0488622 0.0488622 0.0488622