DENVER -- New numbers from Airbnb show just how popular short-term rentals have become in Colorado.
Hosts earned nearly $124 million on the site last year, while more than 700,000 guests took advantage of Airbnb in Colorado.
Many cities have put regulations in place on short-term rentals. Denver requires hosts to have a business license and pay a 10.75 percent lodging tax.
Short-term rental tax collection has become a significant source of revenue for state and local governments.
Based on numbers from 2016, Airbnb hosts in Denver earned $37.3 million. The lodging tax would have produced more than $4 million to the city.
Dan Rowland with Denver's Department of Excise and Licenses said about one-third of the 3,000 Airbnb hosts in Denver are in compliance of the regulations.
Rowland also said the city will be sending out letters to the hosts without licenses next week. They will be given 14 days to comply or will face fines up to $999.
Over the past year, Airbnb reached a number of tax agreements with other cities in Colorado. In October and November, Airbnb began collecting and remitting taxes in Breckenridge, Colorado Springs, Golden and Steamboat Springs.
In Steamboat Springs, where tax collection began in November, $50,000 has been paid to date, according to the site.
The annual earnings for a typical host in Colorado is $6,600 and 34 percent of those are older than 50, according to Airbnb.