condition mean min max ZT0-3 17.471714417500003 16.7892897 18.154139135 ZT4-7 16.630332742500002 15.113759869999999 18.146905615 ZT8-11 17.3471157375 15.945183065 18.74904841 ZT12-15 14.1559135435 12.221553562 16.090273525 ZT16-19 19.512638312500002 18.056910780000003 20.968365845 ZT20-23 25.290394132499998 24.37040628 26.210381984999998