In fact up volume was nearly doubled by down volume. It made up less that 35% of the total of the two. I looked back to 1970 to see other times when up volume was less than 35% of up plus down volume while the S&P 500 closed positive on the day. I was fairly surprised to find only 4 other cases. They were 3/27/80, 1/25/82, 10/4/94, and 3/23/05.
To see what poor breadth on an up day may suggest I then loosened the requirements some. In this case I changed the requirement from 35% up volume to 45% or lower up volume. Below is a summary of the results.
It appears that the weakness in the broad market tends to act as a drag on the S&P over the subsequent two weeks. Whatever was holding the S&P 500 up in the face of the instance-day weakness eventually ends up falling as well.
On another note, the CBI moved up to “6” today. Any higher and we’ll be at levels where I normally being scaling into long index positions.