An annual "report card" that judges the availability and affordability of housing in Greater Boston gives good marks to the city's efforts to increase housing, but lower marks to the suburbs.
In total, the report, The Boston Foundation's Greater Boston Housing Report Card, estimates housing permits in Boston and Greater Boston together are up 12 percent from 2016.
Much of that growth comes from the city of Boston itself. The city is on track to approve nearly 60 percent of permits for buildings with five or more units, and more than 41 percent of all new housing permits in 2017.
By contrast, communities outside of Boston, in total, are set to approve 7 percent fewer units in 2017, from 2016.
"What we need to see is the rest of Greater Boston catching up with the city, learning from the city, and finding out how to permit more quickly and to produce the housing we're going to need throughout the region," said Boston Foundation senior fellow and Northeastern University public policy professor Barry Bluestone, who put together the report card.
The report defines Greater Boston as Essex, Middlesex, Norfolk, Plymouth and Suffolk counties.
The strong economy in the area has created a need for more housing, which is not being met by the current rate of housing development, said Bluestone.
And the growth of the economy has led to an affordability challenge. For example, more than half of the renters in Greater Boston spend more than 30 percent of their income on rent, and more than one-third of owner-occupied households with a mortgage are paying more than 30 percent of their income on housing costs.
Distance to Boston plays a factor in housing affordability. Communities like Cambridge, Lexington, Somerville and Brookline, and Boston neighborhoods like Jamaica Plain and South Boston, have seen their median selling prices of single-family houses rise dramatically from 2005.
At the same time, home sales are down — the report says current estimates for 2017 will forecast a 11.7 percent decline in single-family home sales. If it holds true, it would mean the largest year-over-year decline since 2005.
Bluestone sees little relief in sight under existing housing policies.
"Unless we can get housing supply to match housing demand, there's not much we can do to keep prices from continuing to escalate," he said.
The report card finds 18.3 percent of new housing units permitted by Boston were considered affordable between 2011 and 2016, down from 25.7 percent between 2004 and 2010.
The report recommends more multi-unit housing be approved and tailored to two growing populations: millennials and seniors who are more likely to live in smaller units and by themselves, or with 1 to 2 other people.
The report cites data from the Metropolitan Area Planning Council that estimates that millennials and seniors are the only demographic groups growing in Boston through 2030.
Bluestone suggested the state establish a task force made up of elected officials, leaders in construction and representatives of large employers and universities to push for a new housing model, the so-called "21st Century Village": multi-story, mixed-income buildings near public transit that include some smaller units and community spaces.
These developments would attract millennials and seniors and take pressure off soaring housing costs for existing units, said Bluestone.