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Mass. keeps pace with national growth; Cape Cod reverses population drain

Institute provides online visualizations to ease data analysis

The first data release from the 2020 Census has revealed that Massachusetts is the fastest-growing Northeast state, helped by a population turnaround on the Cape. To aid the general public in analyzing the new numbers, the UMass Donahue Institute has just released several online visualizations to see numbers and changes in population and diversity at the state, county and municipals levels.

Statewide, county and municipal levels

Massachusetts saw its resident population increase by 482,288 people, from 6,547,629 counted in 2010 to 7,029,917 in 2020. This increase of 482,288 people represents growth of 7.4%, from 2010 to 2020 and the largest percentage growth among all Northeast States This growth also represents the fastest percentage growth the state has experienced since the 1960s, when the resident population increased by 10.5% between 1960 and 1970. As context, the Massachusetts population increased by 3.1% from 2000 to 2010 and by 5.5% from 1990 to 2000.

Middlesex County is again the largest county in Massachusetts with a population of 1,632,002, followed by Worcester County at 862,111, and Essex at 809,829. In terms of sheer population numbers, the largest gains in population since the 2010 Census were seen in Middlesex at 128,917 followed by Suffolk at 75,913 and Essex at 66,670. Only two Massachusetts counties, Franklin and Berkshire, lost population between Census 2010 and 2020, with a loss of 343 in Franklin and 2,193 in Berkshire.

According to the Census 2020 results, Boston ranks as the largest city in Massachusetts at 675,647 followed by Worcester at 206,518 and Springfield at 155,929. The state’s two largest cities also ranked first in terms of total population change from 2010 to 2020, with Boston gaining 58,053 in population and Worcester gaining 25,473. The state’s third largest city, Springfield, grew only minimally over the past ten year by 2,869 persons.

Massachusetts island counties are the fastest growers in the state while Barnstable County grows again after population loss

One of the most notable results from the Census 2020 count was the dramatic increase in population in the Cape and Islands region. The island county of Nantucket, which is also the Town of Nantucket, was the fastest-growing county in Massachusetts in terms of percentage change, increasing by 40.1% since the last Census count in 2010. The island county Dukes, which includes Martha’s Vineyard, followed right behind in rank, growing by 24.6%. Even Barnstable County, commonly referred to as “Cape Cod,” moved up in rank from the county with the greatest population loss in the 2000 to 2010 period to the 9th fastest-growing from 2010 to 2020. While last decade Barnstable decreased by 2.9%, this decade it increased by 6.1%.

Despite the downturn in Barnstable County population last decade, the Cape and Islands Region is no stranger to rapid growth. Rapid growth was measured in Cape Cod as far back as the 1930s, when Barnstable County grew by 15.4% compared to a state average of only 1.6% at the time. From the 1940s onward, this growth only accelerated, with rates often four or five times the statewide average. The 1970s in particular were a decade of rapid expansion, with the Barnstable County growing by 53% and Dukes by 46.2%, even as the state was stagnant at just 0.8% in that 1970-1980 period.

“We can’t yet determine whether this intense growth in the Cape and Island region is the result of temporary migration to the region due to the pandemic, including the strong possibility of usual ‘snowbirds’ turning into what I’ll call ‘stay-birds’ in the period around April 1, 2020,” said Senior Research Program Manager Susan Strate, Population Estimates Program at UMass Donahue Institute. “Before the pandemic ever hit, we were hearing anecdotal accounts of more second-home owners on the Cape starting to use their coastal homes as primary residences. In future analyses, we hope to look at population change by age groups, reported occupancy status, and information on how properties are now designated in local assessors’ records to better understand these changes.”

UMass Donahue Interactive Census Maps

See the Institute’s interactive maps: https://donahue.umass.edu/census2020.

Visitors can explore:

  • Population changes (2000-2010) and overall population changes (1970-2020)
  • Racial population shares
  • Housing units (occupied and vacancies)
  • City and Town sortable rankings
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