[An earlier version of this piece appeared in Forbes.com.]

Home prices are skyrocketing in most U.S. markets despite Covid-19, a recession and a shockingly high unemployment rate.

Many analysts are speculating that part of the boom in house prices is caused by Covid-19—that some people are concerned about Covid-19 contagion and don’t want to live in tight, multi-family buildings anymore, so they’re buying single-family homes in the suburbs. Another theory along the same lines is that because working from home has skyrocketed, some people want more space, so they’re buying larger single-family homes, especially if their kids are home all day, too. This seems to be happening in metro New York City, but what about places that weren’t hit as hard by Covid-19 and aren’t as dense as New York City?

Certainly the lower mortgage interest rates are a huge part of the current home price boom. The 30-year fixed-rate mortgage rate the first week of January 2020 was 3.7%. It’s now only 2.9%, according to Freddie Mac. The lower rates make your monthly mortgage payment a lot cheaper, so more people are buying homes. They’re also buying pricier homes.

The monthly principal and interest payment on a $300,000 mortgage would fall by $132 per month when rates fall from 3.7% to 2.9%. Or put another way, for the same monthly principal and interest mortgage payment on a $300,000 mortgage at 3.7%, you could borrow $332,000 at today’s 2.9%. A lot of home buyers are okay with paying a bit more for a house now because their monthly mortgage payment is still less than it would have been last January.

The question is: How much of the current wild housing market is caused by the lower rates and how much is caused by Covid-19 changing the kind of homes people want? Here’s a quick look at one market where I have access to detailed housing data: Phoenix, Arizona.

Contrary to the Covid-is-changing-consumer-demand theory, the number of condos sold via the metro Phoenix MLS in August was up 6% in 2020 compared to 2019, while the number of single-family homes sold was down 2%.

Looking at prices instead of sales, the median price of Phoenix condos sold in August 202o was up a whopping 17% compared to August 2019. For single-family houses, the median price was also up 17%.

It’s only one city, but it doesn’t look like demand is shifting away from living in higher density condos and toward single-family homes.

The main driver of the current real estate market mania is the lower mortgage interest rates, which were in turn caused by the Federal Reserve’s response to Covid-19. According to this quick analysis, Covid-19 didn’t cause Phoenix home buyers to shift away from condo purchases.

What are you seeing in your area? If condo sales are relatively weaker than single-family home sales, that would suggest Covid-19 is changing consumer demand preferences.