condition mean min max ZT0-3 18.840836625 17.47246807 20.209205179999998 ZT4-7 15.0197338725 13.77382226 16.265645485 ZT8-11 23.671407837500002 18.578084920000002 28.764730755000002 ZT12-15 33.509291665 32.77183026 34.24675307 ZT16-19 32.3421369775 32.037665515 32.646608439999994 ZT20-23 34.1577737125 33.75918539 34.556362035