Real estate brokerage firm Redfin recently did an analysis of "mortgage-rate lock data" taken from the analytics firm Optimal Blue. A mortgage-rate lock is an agreement between a lender and a borrower guaranteeing a particular interest rate for a particular period of time.

What's potentially interesting about this data is that (1) approximately 80% of mortgage-rate locks apparently result in an actual home purchase and (2) buyers must specify whether they're applying to secure a rate for a primary home, a second home, or an investment property. So there's a high degree of intent that goes along with these applications.

What Redfin found when they looked at the data is that the growth in demand for second homes is exceeding that of primary homes by quite a wide margin. They argue that this is largely a result of people now working remotely.

But this rise in demand -- at least according to the above data -- appears to have started in the second half of 2019. So I think a few more data points would be helpful in understanding what's really going on. Is what we're seeing more about acceleration than about causation? And what does this look like a year from now?

Chart: Redfin