condition mean min max ZT0-3 15.824689913333334 14.33403494 17.315344886666665 ZT4-7 16.686594358333334 16.553459046666667 16.81972967 ZT8-11 16.304936255 14.887299630000001 17.72257288 ZT12-15 17.5419781 16.94944016 18.13451604 ZT16-19 17.963092 17.41695187 18.50923213 ZT20-23 19.011521695 18.346317983333336 19.676725406666666