Manhattan is glutted with even more luxury condos than most apartment-shoppers realize.

The borough has 7,050 unsold, newly built units, according to a report by Halstead Development Marketing. The bulk of those -- almost 6,000 -- haven’t been formally listed for sale, creating an under-the-radar “shadow inventory.”

The secret supply is a heavy weight on a market in which sales, especially of higher-end properties, have slowed to a crawl. It would take take 74 months -- more than 6 years -- to clear all of Manhattan’s unsold units at the pace of contracts in 2019, the report shows.

The glut is a product of a post-recession construction boom aimed at globe-trotting investors, who now show little interest in collecting lavish Manhattan homes. And most newly built apartments are out of reach for the majority of New Yorkers.

The shadow inventory is largest in the area that includes the Financial District. Those 967 apartments are on top of 96 units that are actively being marketed, the report shows.

This article was provided by Bloomberg News.