condition mean min max ZT0-3 7.6111111110000005 7.6111111110000005 7.6111111110000005 ZT4-7 6.427222222 6.427222222 6.427222222 ZT8-11 6.47 6.47 6.47 ZT12-15 5.52 5.52 5.52 ZT16-19 4.824444444333333 4.824444444333333 4.824444444333333 ZT20-23 4.947777778 4.947777778 4.947777778