Data Analysis Project · University of Washington Bothell

Rising Rent &
Homelessness
in Washington

An analysis of the relationship between housing costs and homelessness across Washington State from 2015 to 2024, using Zillow ZORI data and HUD Point-in-Time counts.

View Code on GitHub View Data
Authors
Alisa Seng Chea, Duke Sarankhuu,
Tarang (TJ) Jammalamadaka
Tools Used
R · ggplot2 · Tableau · Excel
Data Sources
Zillow Research (ZORI) · HUD PIT Count
Time Period
2015 – 2024 (10 years)
+63%
Rent increase
2015 → 2024
+62%
Homelessness increase
2015 → 2024
r=0.78
Correlation coefficient
all years
2021
Key outlier — COVID
eviction moratorium
01

Data Visualizations

Average Monthly Rent
Washington State metros · Zillow ZORI · 2015–2024
Total Homelessness
Point-in-Time count · HUD · 2015–2024
Rent vs. Homelessness — Key Relationship
Each point = one year · Upward trend shows positive association · 2021 is the COVID outlier
02

Key Findings

~60%
Parallel Growth
Both rent and homelessness increased by roughly 60% between 2015 and 2024, suggesting a strong positive association between housing costs and housing instability.
2024
All-Time Highs
Both metrics reached their highest recorded levels in 2024 — average rent at $1,650/mo and 31,554 homeless individuals — indicating that affordability pressures have continued to intensify.
2021
COVID Outlier
Homelessness dropped sharply to 11,511 in 2021 despite rising rent — attributable to COVID-19 eviction moratoriums and federal emergency rental assistance programs protecting tenants.
03

Methodology & Sources

Approach

Monthly ZORI values for all Washington State metros were extracted and averaged by year to produce a single statewide annual rent figure. HUD Point-in-Time counts — a single-night census conducted each January — were used as the homelessness measure.

R was used for data cleaning, reshaping (pivot_longer), and ggplot2 visualization. A Pearson correlation was computed between annual average rent and annual homeless count. The 2021 outlier was identified and analyzed separately given the extraordinary policy context.

Causation caveat: This analysis identifies a correlation, not causation. Homelessness is driven by multiple factors. Rising rent is one contributing pressure among many.

Data Sources

  • Zillow Observed Rent Index (ZORI) — Smoothed, all homes plus multifamily. zillow.com/research/data
  • HUD Point-in-Time Estimates by State, 2007–2024 — U.S. Dept. of Housing and Urban Development. hudexchange.info
  • COVID-19 Policy Context — Rental Housing Association of Washington. rhawa.org/covid-19
  • Emergency Rental Assistance — U.S. Dept. of the Treasury. treasury.gov