BOSTON -- Perhaps it's the law of supply and demand -- too many cars and too few spaces -- but Boston continues to have among the highest rates for monthly parking in the United States, second only to Manhattan.

The median cost for a monthly parking space in Boston is $460, according to a study released Wednesday by Colliers International, a real estate services company. In New York City, a space in downtown Manhattan costs $500 and rises to a whopping $630 per month in Midtown.

The national median for monthly parking is $152 per month.

Parking Cost Survey

Colliers cites a "robust business climate" that places a greater demand for office space and spots to park. The company projects continued price increases in the year ahead.

Residents in the Northeast would have to move west to find more affordable parking. The least expensive city in the survey is Phoenix, where monthly parking is just $35.

Boston also ranks second in the cost of daily parking with an average space costing $33. New York City is again first on this list, with a daily cost of $42 in Midtown.