St. Joe: Demographics & People

St. Joe's population stands at 411 people, in 144 households. Population shrank 2.1% from 420 (2022) to 411 (2024). Median age 33.6 years. (4.8y younger than DeKalb County; 4.6y younger than Indiana). Children under 18 are 28% of the population. Population is 95% White (non-Hispanic) and 3% Hispanic or Latino. The community is relatively homogeneous (Simpson index 0.06). 71% of households are family-led. County is gaining 304 residents per year (2022-2023). County health: 38% adult obesity, 18% smoke.

Population & Trend

Population shrank 2.1% from 420 (2022) to 411 (2024). Estimated 2026 population: ~402 (extrapolated at -1.1%/yr trend). Census Bureau Vintage estimate: 390.

Census data vintage2024
Population43,265 people
Annual growth rate · Population change-2.1%
Annual growth rate · Population (2022)420
Annual growth rate · Population (2024)411
Annual growth rate · Trend categorydeclining
Population411 people
Population Estimate390

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

Age Distribution

Median age 33.6y is 5.3 years younger than the U.S. median (38.9y). Children under 18 make up 28% — above the U.S. share of ~22%.

Age Summary · Median age33.6 years (vs Indiana 38.2y)
Age Summary · Children Pct28.2%
Age Summary · Characteryoung professional
Population under 18116
Median age33.6 years (vs Indiana 38.2y)

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

Race, Ethnicity & Diversity

Of 411 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.06 (0 = single group, 1 = perfectly even distribution); this is read as relatively homogeneous.

White residents405
Hispanic or Latino residents12
Diversity Index · Diversity index (Simpson)5.6%
Diversity Index · Diversity labelrelatively homogeneous
Diversity Index · Groups counted2
Diversity Index · Largest group share97.1%
Hispanic or Latino population3.4%
White (non-Hispanic) population94.9%

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 (7)

(unnamed)
German
(unnamed)
English
(unnamed)
Irish
(unnamed)
American
(unnamed)
Hispanic Total
(unnamed)
Puerto Rican
(unnamed)
Polish

Citizenship & Origin

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

Residents born in this state332
Residents born in another state74
Share born in this state80.8%
Share born in another state19.2%
Native-born U.S. citizens18.0%
Naturalized citizens1.2%
Total foreign-born residents15

Households & Family Composition

144 households. Averaging 2.9 people each — larger than the U.S. average of 2.5. 71% are family households — above the U.S. share of ~65%. Of 104 families, 25% are married couples with children.

Children under 18113
Total families104
Married couples with children26
Single-parent households4
Average household size2.86
Women who gave birth (past year)38.6%
Grandparents living with grandchildren820
Grandparents responsible for grandchildren350
Family households102 households
Households that are families70.8%
Total households144 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. 6.6% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is gaining 304 residents per year on net (IRS migration data).

Moved within the county (past year)6.6%
Migration · People moving in (annual)44,022
Migration · People moving out (annual)43,718
Migration · Net migration (in − out)304
Migration · Population growingYes
Migration · Year2022-2023

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

Disability

Census ACS measures self-reported functional limitations — vision, hearing, mobility, cognitive, self-care, or independent-living. The U.S. baseline disability rate is about 12–13%; rates trend higher with median age.

Residents with a disability35
Disability rate8.2%

Other

Congressional District · District3
Congressional District · FormattedIN-03
Congressional District · Congress118th
Cdc Birth Rate · Fips18,033
Cdc Birth Rate · State Fips18
Cdc Birth Rate · County Fips33
Cdc Birth Rate · CountyDe Kalb
Cdc Birth Rate · Birth Rate24.8%
Cdc Birth Rate · Lower Ci21.00
Cdc Birth Rate · Upper Ci29.00
Cdc Mortality · Fips18,033
Cdc Mortality · CountyDeKalb County
Cdc Mortality · Urban RuralMicropolitan
Cdc Mortality · Total Deaths 2020 20231,388
Cdc Vaccination · Fips18,033
Cdc Vaccination · CountyDeKalb County
Cdc Vaccination · Dose1 Pop Pct48.0%
Cdc Vaccination · Series Complete Pct44.1%
Cdc Vaccination · Booster Pct49.8%
Cdc Vaccination · Population 201943,475
Cdc Vaccination · Metro StatusNon-metro
Family Score · Score7.50
Family Score · Schools13
Family Score · Children Pct28.2%
Family Score · Ratingexcellent
Town Summary · Key Factspopulation 411, declining, young professional, middle-class, blue collar
Town Summary · Population411 people
Town Summary · CountyDeKalb County

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