St. Mary's: Demographics & People

68 people call St. Mary's home, in 58 households. Population shrank 47.7% from 130 (2022) to 68 (2024). Median age 64.1 years. (15.0y older than Clear Creek County; 26.2y older than Colorado). Population is 100% White (non-Hispanic). The community is relatively homogeneous (Simpson index 0.00). 26% of households are family-led. County is losing 53 residents per year (2022-2023). County health: 26% adult obesity, 12% smoke.

Population & Trend

Population shrank 47.7% from 130 (2022) to 68 (2024). Estimated 2026 population: ~39 (extrapolated at -23.8%/yr trend). Census Bureau Vintage estimate: 14.

Census data vintage2024
Population9,397 people
Annual growth rate · Population change-47.7%
Annual growth rate · Population (2022)130
Annual growth rate · Population (2024)68
Annual growth rate · Trend categoryshrinking
Population68 people
Population Estimate14

Sources: Census ACS 5-Year 2023, Table B01003  ·  Refreshed 2026-04-12

Age Distribution

Median age 64.1y is 25.2 years older than the U.S. median (38.9y).

Age Summary · Median age64.1 years (vs Colorado 37.9y)
Age Summary · Characterretirement community
Median age64.1 years (vs Colorado 37.9y)

Sources: Census ACS 5-Year 2023  ·  Refreshed 2026-04-12

Race, Ethnicity & Diversity

Of 68 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.00 (0 = single group, 1 = perfectly even distribution); this is read as relatively homogeneous.

White residents130
Diversity Index · Diversity labelrelatively homogeneous
Diversity Index · Groups counted1
Diversity Index · Largest group share100.0%
White (non-Hispanic) population100.0%

Sources: Census ACS 5-Year 2023  ·  Refreshed 2026-04-12

Ancestry

Self-reported ancestry from Census ACS — what residents report as their ethnic origin, separate from race. Counts can exceed population because people can list multiple ancestries.

Top (2)

(unnamed)
German
(unnamed)
English

Citizenship & Origin

Where residents were born and their citizenship status (Census ACS).

Residents born in another state68
Native-born U.S. citizens100.0%
Total foreign-born residents419

Households & Family Composition

58 households. Averaging 1.9 people each — smaller than the U.S. average of 2.5. 26% are family households — below the U.S. share of ~65%. Of 22 families, 100% are married couples with children.

Children under 1841
Total families22
Married couples with children22
Average household size1.88
Grandparents living with grandchildren8
Family households15 households
Households that are families25.9%
Total households58 households

Sources: Census ACS 5-Year 2023  ·  Refreshed 2026-04-12

Residential Stability & Migration

How long residents have lived here and where they came from. 11.8% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is losing 53 residents per year on net (IRS migration data).

Lived in same home a year ago68.0%
Moved within the county (past year)11.8%
Migration · People moving in (annual)8,722
Migration · People moving out (annual)8,775
Migration · Net migration (in − out)-53
Migration · Year2022-2023

Sources: IRS SOI Migration 2021-2022  ·  Refreshed 2026-04-12

Other

Congressional District · District2
Congressional District · FormattedCO-02
Congressional District · Congress118th
Cdc Birth Rate · Fips8,019
Cdc Birth Rate · State Fips8
Cdc Birth Rate · County Fips19
Cdc Birth Rate · CountyClear Creek
Cdc Birth Rate · Birth Rate8.7%
Cdc Birth Rate · Lower Ci4.60
Cdc Birth Rate · Upper Ci14.90
Cdc Mortality · Fips8,019
Cdc Mortality · CountyClear Creek County
Cdc Mortality · Urban RuralLarge fringe metro
Cdc Mortality · Total Deaths 2020 2023179
Cdc Vaccination · Fips8,019
Cdc Vaccination · CountyClear Creek County
Cdc Vaccination · Dose1 Pop Pct57.5%
Cdc Vaccination · Series Complete Pct51.1%
Cdc Vaccination · Booster Pct58.7%
Cdc Vaccination · Population 20199,700
Cdc Vaccination · Metro StatusMetro
Family Score · Score2.00
Family Score · Schools2
Family Score · Ratinglimited
Town Summary · Key Factspopulation 68, shrinking, retirement community, lower-income, white collar
Town Summary · Population68 people
Town Summary · CountyClear Creek County

Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade