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Aging in Colorado Part 1: Why is Colorado Aging So Quickly?

Sep 20, 2016 • Colorado State Demography Office

It’s no secret that Colorado’s population is getting older. Our state’s aging population has been covered in news stories and data analysis by everyone from the Denver Post to the US Census Bureau, and with good reason. Between 2010 and 2015, Colorado’s growth in its 65 plus population was 3rd fastest in the US at over 29%. Compare this to our 4th place in overall growth (8.5%), and it’s easy to see why this topic has garnered so much attention.

But what does an older population actually mean for Colorado, and why is it happening? To answer this, we have to start at the beginning, and look at the state’s total population.

Table: Colorado Population by Age

In 2010 Colorado’s population was 5,029,196, a 17% increase over the previous decade. Between 2010 and 2015 the state increased by another 427,000, or 8.5%. Even more interesting is that since 2000 Colorado’s 65+ population has grown faster than the total state population- the first time this has happened in Colorado’s history!

Why is CO aging so fast?

To put it simply, the reason Colorado’s 65+ population is growing so fast is because it was relatively small to begin with. In 2000, only 10% of our population was 65+ (compared to 12% in the US as a whole and 18% in Florida, to put it in perspective). Starting with that relatively small number, and then factoring in migration and aging (especially of the Baby Boomers) explains the significant change.

Between 2000 and 2010 migration was only responsible for approximately 6,000 of the 133,552 increase in Colorado’s population 65+, and that trend has continued since. The rest of the increase we’ve seen has been due to people aging into the 65+ age cohort.

People migrate to Colorado from all age groups, but as this chart shows, there is a relatively small share migrating over the age 65 (to the right of the red line) compared to other age groups. Because the majority of the migrants to Colorado are young, our overall population has historically skewed in that direction as well. It has taken decades for the large group of young migrants from the 1970s to age to 65. Migration was responsible for 70% of the population increase between 1970 and 1980, the majority of whom were 25-35 and part of the Baby Boomer generation. This explains why aging (not migration) is now having the largest effect on our 65+ population.

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Data sources: US Census Bureau and State Demography Office