In the past decade Dennis lost 1,766 year-round residents. We are now beginning to acquire information available to allow us to understand the nature of this population shift.
The under 18 population dropped by 720 people in the decade. This is nearly a 27% drop in this segment of the population in the decade. Given overall population dropped by only 11.1%, and in 2000 the under 18 population was 17% of the total population in Dennis, it is safe to say that there are fewer young people in Dennis in 2010 than there was in 2000.
Now that the Census has started to release information about the age of people in town, we can see that families with young children were leaving town. If we attempt to track the population in 2000 that was under 15 years old, we find that there were 2,190 people in this age group. Ten years later, these children make up the Dennis population between 10 and 24 years old. The 2010 population in this age cohort drops by 613 people. Obviously some people leave for college in this age group, so, if we break it down even more finely, we see drops in every age cohort. Children under 5 in 2000 become the 10 – 14 year old age group in 2010, this age cohort drops by 146 children. Similarly the 5 – 9 year age cohort in 2000 sees 239 of these children gone in the 15 to 19 age cohort.
We also know that the 18 and over population dropped as well, by 1,046 people, or 6.5%. This drop in year-round population is nowhere near as dramatic as in the younger age group.
The population that was between 20 and 39 years old in 2000 make up the 30 to 49 age cohort in 2010, this age cohort, those most likely to have had children living in Dennis in 2000, saw a drop of 895 people. Essentially illustrating a significant out-migration of people of child bearing age leaving the town.
Interestingly, we lost significant population in the oldest age cohorts, decade over decade as well. The 70 plus population in 2010, which represents the 60 plus age cohort in 2000, shows a drop of 1,248 people. This change includes, obviously deaths, but is also represents others who have simply chosen to not winter on the Cape any longer. Looking at it closely, we see that the 60-64 age cohort in 2000, drops by 179 people by 2010 when they are between 70 and 74. Similarly, the 65 -69 age cohort in 2000 drops by 327 people by 2010 when the are 75 – 79 years of age.
So, with all these people leaving, where did we gain population? That would fall squarely in the age cohort that was between 40 and 60 years old in 2000. This age cohort grew by 509 people during the past decade, meaning more people moved into Dennis in this age cohort than left during the decade, as they all grew ten years older.
Ultimately, the loss of younger people, and the growth in people between 50 and 70, results in a significantly older Dennis the median age was 49.4. In 2010 the median age has jumped to 55.1. Men are younger than women, with a male median age of 53.2 (up from 47.9 in 2000) and female median age of 56.8 (up from 50.7 in 2000).
We also know that occupied housing units dropped, by 576 units, or 7.7% of the housing units occupied in 2000 no longer being occupied. However, in a strange twist, total housing units grew by 1,481 housing units, or 10.5%. Essentially boiling down to a vacancy level of 55.5% of all housing units being vacant on Census day. The breakdown between seasonal housing and vacant housing is also now available. Dennis seasonal housing has grown to 50.9% of all housing units. Looking at this figure, we can determine a number of things.
• The year-round vacant housing in Dennis change very minimally in the past decade.
• The housing units which were occupied in 2000 and now appear as vacant in the 2010 Census have been converted to Seasonal Housing.
• New housing added since 2000, 1,481 housing units, reflect additional growth in the seasonal population of the town.
In 2000 Dennis had 2.12 people per occupied year-round housing unit. In 2010 this number has dropped to 2.05 people, clearly illustrating a drop in household size – i.e. reflective of the loss of children in Dennis. Seasonal population, those owning second homes in Dennis is, quite likely, similar to the Dennis population. Perhaps a few more children, but not dramatically so. About 80% of the seasonal housing units appear to be seasonally owner occupied. Rental seasonal housing units, are targeted, based upon rental permits, to a much higher occupancy rate.
If we considered only the population in housing units (excluding hotels, Recreational Vehicles and cottages), Dennis had an estimated summer population of 37,785 people in 2010 as opposed to one of about 28,800 in 2000, a growth in summer population of 8,985 people or roughly 31%.
Finally, when residents of area hotels, recreational vehicles and those who work in Dennis, the town has a summertime daytime population approaching if not exceeding 50,000 people.