condition mean min max ZT0-3 10.548615 10.548615 10.548615 ZT4-7 10.250281999999999 10.250281999999999 10.250281999999999 ZT8-11 10.1786295 10.1786295 10.1786295 ZT12-15 9.1830365 9.1830365 9.1830365 ZT16-19 10.431353999999999 10.431353999999999 10.431353999999999 ZT20-23 9.9238265 9.9238265 9.9238265