What the 1930s redlining maps predict about Los Angeles today
Between 1935 and 1940 the Home Owners' Loan Corporation graded American neighborhoods from A to D to guide mortgage lending. The D areas, outlined in red on the original maps, were overwhelmingly the Black, immigrant and working-class districts, and the grades were explicit about it. Lending followed those lines for decades afterwards.
Those maps are ninety years old. The question this page answers is a narrow, checkable one: when you lay the graded areas over the present-day neighborhood index, what do they measure like now? Every figure below is read from the same artifact behind the interactive map, so anyone can reproduce it.
The short answer: areas graded A still sit under 16% tree canopy against 3% in areas graded D, and the gradient runs the same direction on every measure we hold: pollution exposure, rent, and the adult earnings of children raised there.
Present-day measures by 1930s grade
Averaged across the index hexagons whose centre falls inside each graded area.
| Measure | A | B | C | D |
|---|---|---|---|---|
| Areas measured | 130 | 189 | 472 | 225 |
| Tree canopyshare of ground under tree cover | 16% | 9% | 5% | 3% |
| Environment scoreair, traffic and canopy, 0-100 against the region | 63 | 47 | 35 | 24 |
| Pollution exposuresix CalEnviroScreen measures, higher = more exposure | 47 | 56 | 61 | 70 |
| Combined burdenexposure together with rent burden | 38 | 51 | 61 | 68 |
| Economic mobilityadult outcomes for children raised there | 66 | 48 | 34 | 22 |
| Median rentACS median gross rent | $2,650 | $2,100 | $1,750 | $1,625 |
| Median home valueACS median value, top-coded at $2,000,001 | $1,570,000 | $1,015,000 | $725,000 | $665,000 |
Grades read A “Best”, B “Still desirable”, C “Definitely declining”, D “Hazardous”. Those are the HOLC's own labels.
What this does and does not show
This is a correlation between a historical grade and a present-day measurement. It does not isolate redlining from everything else that shaped these areas over ninety years, and nothing here should be read as a single cause producing a single effect.
The grades only cover the parts of the region HOLC surveyed in the 1930s, which is a small share of today's built-up area. 1,016of the index's hexagons. Everything outside those boundaries is absent here, including nearly all of Orange County.
A hexagon is about a kilometre across and a graded area can be smaller, so each hexagon is counted toward whichever grade contains its centre. Hexes are assigned to a HOLC grade by centroid containment; a hex straddling two graded areas counts only toward the one holding its centre. Present-day figures are read from explore-features.json so they match the Explorer exactly. Grades cover only the parts of the region HOLC surveyed in the 1930s, which is far from all of it.
Sources. Mapping Inequality: Redlining in New Deal America (Nelson, Winling, Marciano, Connolly et al., University of Richmond Digital Scholarship Lab), digitized HOLC area descriptions, 1935-1940. Present-day figures from the Saktoo Neighborhood Index, compiled 2026-08-12.
Terms. The HOLC grades are published by the Digital Scholarship Lab at the University of Richmond under a CC BY-NC-SA 4.0 licence, which restricts commercial reuse; cite them as Nelson, Winling, Marciano, Connolly et al., “Mapping Inequality,” American Panorama. The present-day Saktoo measures on this page are covered by the terms on our data page and are not redistributed with the HOLC grades attached.
Go deeper
- The pollution and rent-burden map
The same environmental story on the live map, without the historical layer.
- Tree cover, clean air, little traffic
LA and Orange County neighborhoods ranked on air quality, traffic exposure and tree canopy, from CalEnviroScreen and national land-cover data.
- Where growing up led to higher adult earnings
LA and Orange County neighborhoods ranked on Opportunity Atlas outcomes: what children raised in each area earned as adults, from Census-linked tax records.