condition mean min max ZT0-3 8.3172356285 7.798259633000001 8.836211624 ZT4-7 5.8178238675000005 4.73054926 6.905098475000001 ZT8-11 8.11679663025 7.611819529 8.6217737315 ZT12-15 7.398458498 7.097162587 7.6997544090000005 ZT16-19 11.09257554775 8.703886330500001 13.481264764999999 ZT20-23 17.389425062500003 17.093389475000002 17.68546065