The year-round population of Martha’s Vineyard swelled by 25 per cent in the past 10 years, topping 20,000 people last year, according to 2020 U.S. Census figures released Thursday.

Every Island town saw double-digit population increases, ranging from an 18 per cent boost in Oak Bluffs to a 41.2 per cent jump in tiny Aquinnah, from 311 to 439. The Island as a whole went from 16,460 people in 2010 to 20,600 in 2020.

The decennial Census was an effort to count the number of people living or staying in a given location as of April 1, 2020, just a few weeks after the Covid-19 pandemic hit, suggesting that the Island’s current population numbers may be even higher. Exact figures remain elusive, but data from the Steamship Authority and elsewhere suggest that several thousand people moved to the Island full-time over the past year.

While Massachusetts as a whole grew by about seven per cent, the most of any New England state, some western Massachusetts towns experienced losses while others in the Boston area showed gains.

By far the greatest growth was on the Cape and Islands.

Nantucket gained almost as many new residents as Martha’s Vineyard, with 4,083 more people recorded in 2020 than a decade earlier.

While non-white residents have increased, both Martha’s Vineyard and Nantucket remain predominantly white at 78 per cent and 69 per cent respectively.