condition mean min max ZT0-3 2.124175 1.99641 2.2519400000000003 ZT4-7 3.1377750000000004 3.1377750000000004 3.1377750000000004 ZT8-11 4.360754999999999 4.360754999999999 4.360754999999999 ZT12-15 0 0 0 ZT16-19 3.602405 3.602405 3.602405 ZT20-23 3.168135 3.168135 3.168135