AgePyramids

Overview

This Shiny R application plots age pyramids from population estimates (1970–2023) produced by the U.S. Census Bureau’s Population Estimates Division. The focus is on state and national data from 1970 to 2023.

AgePyramids

Population Estimates

• Postcensal Estimates: Calculated after each decennial census using data on births, deaths, and migration.
• Intercensal Estimates: Adjust postcensal figures to align with the subsequent census count. The adjustment is distributed across the decade to match April 1 census totals.

Population estimates reflect the population as of July 1 each year, which may differ from April 1 census counts during census years.

Data Sources

Data are pulled from publicly available datasets. The following URLs download portions of the data used.

• 1970-1979
• 1980-1989
• 1990-1999
• 2000-2009, Vintage 2011
• 2010-2019, Vintage 2020
• 2020-2023, Vintage 2023

The vintage corresponds to the last year available in the time series estimates. File organization differs by year or state.

Data Preparation in R

• The application uses DuckDB, a database using columnar-based storage, offering strong compression and high-speed queries.
• Queries are performed using the duckplyr extension in R, which supports lazy evaluation—results are only materialized when needed.