An older-adult geography of New York · under-18 map · where they overlap

Where the elders are,
2000 to 2023

Between 2000 and 2023 the region’s population aged 65 and older grew from 1.46 million to 2.03 million — a gain of about 570,000 (+39%). Within that total, the five boroughs gained 300,000 seniors (+34%) and the inner-ring suburbs gained 270,000 (+47%). The mirror image of the child story: as the under-18 count fell by hundreds of thousands, the 65-plus count rose by roughly the same magnitude. The map below shows where the elders are now — aging in place, moving in, or both.

Age group
Measure ?
View Map colors show change in density between two years.
Years or pick → Scrub end year

2000→2023

Change in seniors per square mile, by 2010 census tract. Red = gain, blue = loss, white = within ±10%.  ·  Click a or for the story behind a notable tract.
Methodology

Data. Counts of persons aged 65 and older by tract for 2000, 2010, 2020 (decennial census, table P012 in 2000 and 2010 SF1, P12 in 2020 DHC) and 2011 through 2023 (American Community Survey 5-year estimates, table B01001). The 65+ count is the sum of six male and six female age cells (65–66, 67–69, 70–74, 75–79, 80–84, 85+). Each year between 2011 and 2023 is a measured ACS estimate. The 2001–2009 gap between decennials is linearly interpolated.

Why 2000–2023 (and not 1970–2023). The companion under-18 map covers 1970 forward because NHGIS publishes a time-series table for “persons under 18” with tract counts already crosswalked to 2010 boundaries. There is no equivalent ready-made time-series table for 65+, so extending the senior map back to 1970 requires a fresh NHGIS extract plus an area-weighted crosswalk on the historical tract polygons. We’ve started with the 2000–2023 window (entirely available from the Census API) because that is also the most editorially interesting span for seniors — it covers the entire boomer-cohort transition into retirement age. A 1970–2023 backfill is on the to-do list.

Age-group filter. The “Age group” chip row lets you restrict the map, totals, and ranked lists to one of three bands: 65–74, 75–84, or 85+. Each is a direct sum of the underlying P012/P12/B01001 cells — never interpolated.

Geography. The study area is the five boroughs of New York City plus every county sharing a land or water border with NYC: Westchester and Nassau (NY); Bergen, Hudson, Union, and Middlesex (NJ). Everything is rendered on 2010 census tract boundaries. Tract polygons are clipped against TIGER/Line AREAWATER (rivers, harbor) and AREALM (parks, cemeteries, airports, and military installations) so non-residential land is not painted by the choropleth. Neighborhood labels in the ranked lists come from NYC Planning’s 2020 Neighborhood Tabulation Areas (inside the five boroughs) and TIGER PLACE 2020 (incorporated and census-designated places elsewhere).

Density. Seniors per square mile = count ÷ land area in sq mi. Land area is computed from 2010 TIGER cartographic boundaries projected to EPSG:2263 (NY State Plane, Long Island, survey feet). Tracts under 0.005 sq mi (airports, parks, water) are excluded.

Share 65+. The “Share 65+” measure divides the count of residents 65 and older by the tract’s total population and reports a percent. This controls for overall density — a tract with 2,000 seniors and 8,000 other residents scores the same as one with 200 seniors and 800 others. Denominators come from decennial table P012/P12 (2000, 2010, 2020) and ACS B01001 (2011–2023), interpolated linearly across the 2001–2009 gap. In snapshot mode the map colors each tract by its share. In delta mode the map colors by percentage-point change (a tract going from 25% to 20% shows as −5 pp, not −20%). Tracts with fewer than 50 seniors or fewer than 200 people total are masked.

Change calculation. The map colors each tract by percent change in density between the “from” and “to” year. The ranked “biggest gainers” and “biggest losers” lists use absolute change (seniors added or lost), not percent change, because percent change is unstable on small bases. The ranked lists also aggregate all tracts within a neighborhood so the number reported is the neighborhood-wide change, not a single cherry-picked tract inside it. Neighborhoods with fewer than 200 seniors at both endpoints are excluded.

Masking low-count tracts. Tracts with fewer than 50 seniors in both the “from” and “to” year are drawn in neutral gray rather than colored. Without this mask the map would be dominated by parks, cemeteries, and institutional sites where the AREALM clip didn’t fully remove the polygon. Totals and ranked lists are unaffected.

Caveats. (1) ACS 5-year estimates carry margins of error at the tract level. The ranked lists should be read as order-of-magnitude, not precise; year-over-year wiggles in a single tract often fall inside the ACS error bar. (2) Tract GEOIDs for ACS endyears 2020 through 2023 use 2020 boundaries; where a 2020 GEOID differs from its 2010 counterpart the ACS value joins the 2010 tract by exact string match. (3) The parks/cemeteries/landmarks clip relies on TIGER AREALM, which is incomplete in urban areas. The low-count mask (above) compensates. (4) Aging-in-place and in-migration look identical in this data — you can see that a tract’s 65+ population grew, but not why. The story markers on the map propose specific mechanisms (NORC, retirement community, postwar suburb, etc.) based on knowledge of those neighborhoods, not from the data itself.

Sources. U.S. Census Bureau via api.census.gov. Companion site: where the children went, 1970–2023. Source code: github.com/joshgreenman1973/nyc-senior-density.