condition mean min max ZT0-3 16.457055 8.836015 23.023899999999998 ZT4-7 13.99055 13.99055 13.99055 ZT8-11 6.2401 6.2401 6.2401 ZT12-15 15.85655 6.5339 25.1792 ZT16-19 12.527225000000001 12.527225000000001 12.527225000000001 ZT20-23 4.6923 4.6923 4.6923