Boston is nation’s second-tightest rental market

Just 2.6 percent of apartments here were empty in the second quarter, according to new Census Bureau figures.Bill Greene/Globe Staff/File

These are good days to be a landlord in Greater Boston.

The region is one of the tightest rental markets in the country, according to new data from the Commerce Department this week, and the homeownership rate has fallen to its lowest level in at least a decade.

Just 2.6 percent of apartments here were empty in the second quarter, according to new figures from the Census Bureau. Among the nation’s 25 biggest metro areas, only San Diego recorded a lower figure.

And the region’s homeownership rate, which had held relatively stable around 66 percent for several years even as the nation’s plunged in the aftermath of the housing crash, sunk for the second straight quarter to 58.2 percent. That’s the lowest since the Census began counting in 2005.

While the numbers reflect the hard time many Bostonians have buying a house in this pricey market, experts say they may also herald some good news: A surge of young adults moving to Boston, and out of their parents’ house, as the economy improves. They may not be buying houses just yet. But they’re paying rent.