The rate on a 30-year fixed mortgage fell below 3% this week, according to mortgage finance company Freddie Mac. This is the first time that’s happened in the past 50 years. For some people, it’s an opportunity to refinance their existing mortgages.

To lock in these low rates, Fannie Mae chief economist Doug Duncan says people will refinance almost two trillion dollars worth of mortgages this year, and could refinance another trillion in 2021.

“Those are huge volumes of people taking advantage of an opportunity to lower their monthly costs,” he says.

Banks and mortgage companies earn fees when people refinance, but Duncan says companies have had trouble keeping up with demand.

If by next year, companies figure out how to better handle the wave of refinancing, Duncan adds that “mortgage rates are probably likely to get in the 2.75 percent range.”

Not everyone can take advantage of low rates, and with the pandemic, there aren’t many homes for sale right now for anyone looking to buy.

Mark Fleming, chief economist at First American, says “everyone’s in big bidding wars over the few that are out there,” but also notes that home owners don’t have many incentives to sell when they can lock in cheap rates as well.