condition mean min max ZT0-3 7.662108673833334 7.4959778450000005 7.8282395026666665 ZT4-7 9.552725293 9.282887415000001 9.822563170999999 ZT8-11 8.176747257666667 7.679339355333334 8.67415516 ZT12-15 9.50247312 8.167784705999999 10.837161534 ZT16-19 9.299850255333332 8.174381466333333 10.425319044333333 ZT20-23 10.258091610166666 8.544101787 11.972081433333333