Housing Forecast Methodologies
Cost Burden Methodology
Cost Burden Methodology
This methodology classifies renter and owner households into three cost-burden categories — not burdened, cost burdened, and severely cost burdened — and rebins them across six Area Median Income (AMI) groups for consistent cross-geography comparison.
Burden Categories
A household is classified by the share of gross household income spent on gross monthly housing costs:
| Category | Definition |
|---|---|
| Not burdened | Less than 30% of income on housing |
| Cost burdened | 30% to 50% of income on housing |
| Severely cost burdened | More than 50% of income on housing |
The 30% threshold follows the long-standing HUD affordability standard, the same definition used in the housing affordability methodology. Households whose ratio is not computed by the Census Bureau (typically because reported income is zero or negative) are counted as "Not burdened" for the purposes of this chart.
Source Tables
Cost burden is reported separately for renters and owners, in two cross-tabulated ACS tables. Each table breaks households down by their household income range and, within each range, by the gross housing-cost-to-income ratio.
| Source | Description | Income bins | Burden categories per bin |
|---|---|---|---|
| ACS B25074 | Household income by gross rent as a percentage of household income (renters) | 7 bins | 8 ratio categories + total |
| ACS B25095 | Household income by selected monthly owner costs as a percentage of household income (owners) | 8 bins | 8 ratio categories + total |
Within each income bin, the eight ratio categories are: less than 20%, 20-25%, 25-30%, 30-35%, 35-40%, 40-50%, 50% or more, and "not computed." The chart collapses these to the three burden categories above.
AMI Rebinning
The native ACS income bins do not align with AMI groups, so household counts are reapportioned from the source income bins to the six AMI groups via proportional overlap.
For each geoid the local AMI thresholds are derived from HUD Income Limits (joined via the GeoHudMapping table for the latest HUD vintage). If no HUD value exists for the geoid, the chart falls back to ACS B19113 (Median Family Income) stepped forward to the HUD vintage by the per-capita-wage-growth ratio between the two years.
The six AMI groups are:
| AMI Group | Range |
|---|---|
| 1 | 0–30% AMI |
| 2 | 30–60% AMI |
| 3 | 60–80% AMI |
| 4 | 80–100% AMI |
| 5 | 100–120% AMI |
| 6 | >120% AMI |
Rebinning is performed by the shared rebin_counts helper, which distributes counts from the source bins to the target bins in proportion to the overlap of the dollar-income intervals.
Combining Renters and Owners
Renter and owner counts are computed independently and then summed bin-by-bin per AMI group, yielding a single household count per (geoid, AMI group, burden category) tuple.
Output Table
| Column | Description |
|---|---|
geoid | Geography identifier |
income_group | One of the six AMI group labels |
no_burden | Households not burdened in this AMI group |
cost_burdened | Households 30–50% burdened |
severely_burdened | Households >50% burdened |
Data Sources
| Component | Source | Table |
|---|---|---|
| Renter cost burden | U.S. Census ACS | B25074 |
| Owner cost burden | U.S. Census ACS | B25095 |
| Median family income (fallback) | U.S. Census ACS | B19113 |
| AMI thresholds | HUD Income Limits | (via GeoHudMapping) |
| ACS-to-HUD-vintage step factor | FRED per-capita wage growth | (derived) |