condition mean min max ZT0-3 15.01425 15.01425 15.01425 ZT4-7 10.939395000000001 10.939395000000001 10.939395000000001 ZT8-11 11.44185 11.44185 11.44185 ZT12-15 13.830850000000002 13.830850000000002 13.830850000000002 ZT16-19 15.50435 15.50435 15.50435 ZT20-23 16.54565 16.54565 16.54565