Norwich apartment rents rose the fastest in the state in January, while Rocky Hill renters benefited from the state’s largest decline in average monthly apartment costs.

A report released Monday by Rent Cafe says rents rose in 16 of Connecticut’s 21 largest multifamily markets in January, with Bridgeport and Norwalk ranking second and third with 0.8 percent increases.

Stamford remains the most expensive market for renters in the state, averaging $2,393 per month following a 0.1 percent decline in January. Waterbury is the most affordable market, with average rents of $950. And in the state’s most populous city of Bridgeport, average rents rose 0.8 percent to $1,121.

Stamford apartments are the state’s most expensive for renters, with an average rent of $2,393, followed by apartments in Norwalk, where the average monthly rent sits at $2,352. 

The Rent Cafe report is based upon a telephone survey by Yardi Matrix of market-rate apartment complexes with 50 or more units.

Nationwide, rents rose 3 percent, the slowest pace in 18 months. Rent Cafe projects continuing increases in 2020, amid a rising number of renters nationwide and influx of high-earning individuals into the apartment market.

But an economics professor said apartment demand reflects factors such as people priced out of the for-sale housing market, particularly in pricey coastal cities.

“Respondents to Fannie Mae’s National Housing Survey consistently report that they would prefer to own rather than rent. The rise in rentals is more likely driven by constraints rather than preferences,” Benjamin Keys, a professor at The Wharton School of Business, said in a statement. “First, house prices are extremely high, especially in the places with the most desirable labor markets.”

Other factors increasing demand for apartments are tight mortgage standards and student loan burdens on Millennials, Keys said.