Contra Costa County, California
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ZIP/ZCTA areas can cross city and county boundaries. Each row describes its ZIP/ZCTA area, not the city as a whole. These values are not combined into a city estimate.
| ZIP/ZCTA | Population | Median household income | Median monthly gross rent | Owner-occupied share |
|---|---|---|---|---|
| 94528 | 1,049 | $207,500 | — | 100.0% |
Source: U.S. Census Bureau American Community Survey (ACS), 2020–2024 five-year estimates, via Realie. Measurement period: –. Published by the Census Bureau on ; published by Realie on . These are five-year estimates, not a measurement of current conditions. — indicates unavailable or suppressed data.
Recorded property characteristics and residential parcel-sale records for Diablo, CA. Sale amounts describe recorded transfers, not asking prices or appraisals. Each measure uses records with that information available.
Sale records use the AVM's residential, amount, floor-area, year-built, price-per-area, deed, buyer-relationship and distress filters. Known multi-parcel deals are also excluded. Unknown package flags are not proof of a single-parcel sale. Counts represent eligible parcel sale records. Recorded annual averages require at least 10 eligible sales. Projections must have enough history and pass checks against earlier recorded sales. Recent sales can be underreported; different coverage between years can affect the changes.
City measurements cover the selected county's portion of the city.
Calendar 2025 recorded sales versus calendar 2026 model projections. Both years cover January 1–December 31. Change compares the 2026 projection with the recorded 2025 value. Annual average amounts weight each month by its sales count; they are not monthly medians.
| Metric | 2025 | 2026 projected | Change (%) |
|---|---|---|---|
| Residential sale records | 20Recorded | — | — |
| Average recorded sale amount | $3,666,650Recorded | — | — |
Projections are not confirmed transactions or property valuations. Recent sales can be underreported; different coverage between years can affect the change. Unsupported values remain unavailable. Ranges reflect historical model errors, not confidence intervals. Annual comparison calculated . Assumed observation cutoff: May 2026; not verified completeness.
| Measure | Diablo, CA | Contra Costa County, CA |
|---|---|---|
| Median recorded sale amount | $2,672,750 | $790,000 |
| Recorded amount, 10th percentile | $1,765,000 | $430,000 |
| Recorded amount, 90th percentile | $6,325,000 | $2,000,000 |
| Average recorded floor area (sq ft) | 4,185 | 2,059 |
| Average recorded bedrooms | 4.3 | 3.3 |
| Average recorded bathrooms | 3.9 | 2.3 |
| Median year built | 1975 | 1977 |
| Condominium share of properties | 1.8% | 9.1% |
Diablo, CA: Recorded median and percentile amounts: May 7, 2025–Oct 28, 2026.
County input file published Oct 23, 2026. Calculated . Published . Dataset last refreshed: .
Contra Costa County, CA: Recorded median and percentile amounts: May 7, 2025–Oct 28, 2026.
County input file published Oct 23, 2026. Calculated . Published . Dataset last refreshed: .
Source: Realie property-record aggregates. Input publication and calculation dates do not establish complete transaction coverage. Missing measures are shown as — or omitted.
These use different periods from the calendar-year comparison. Estimates extend parcel-record counts and recorded amounts; they are not confirmed current transactions or individual-property values.
No supported recent-period estimates are available for this area. Recorded statistics above remain available.
Transaction coverage has not been verified. Known multi-parcel deals are excluded; missing package flags do not establish that every remaining sale covers one parcel. Amount change compares monthly record medians, not the appreciation of the same homes. Ranges reflect historical model errors; they are not confidence intervals and can exclude the point estimate. Assumed observation cutoff: May 2026; not a verified completeness date.
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