Every quarter, I track the 13F filings at the SEC. These are the reports filed by money managers of all stripes that show what the funds owned during the most recent quarter. When you compare the current list to the prior quarter, you come away with a clear picture of what institutions are buying for their customers and themselves.

When I started in the business, it took several days past the deadline to get a copy of the filings. I would go through the current and previous filings with a ruler and a yellow highlighter to track the changes. It was...