condition mean min max ZT0-3 17.4144298575 17.290432405 17.53842731 ZT4-7 7.64457836875 7.478517508 7.8106392295 ZT8-11 12.346896749 8.464754873 16.229038625 ZT12-15 22.8524926775 19.034070975 26.67091438 ZT16-19 18.723680395 18.32062164 19.12673915 ZT20-23 18.821366587500002 17.888569760000003 19.754163415