condition mean min max ZT0-3 30.89535 30.89535 30.89535 ZT4-7 20.141 20.141 20.141 ZT8-11 15.41615 15.41615 15.41615 ZT12-15 22.6547 22.6547 22.6547 ZT16-19 28.14945 28.14945 28.14945 ZT20-23 36.7499 36.7499 36.7499