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Our site brings together key population and socioeconomic data so you can better understand different communities across California. We rely on two main sources: official 2020 Census numbers (with state adjustments) for population counts and demographics, and the American Community Survey (ACS) for everything else—such as income, education levels, and housing.

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2020 Population Data (Block-Level)

Our population data is taken from California’s Statewide Database , which provides the official Adjusted P.L. 94-171 Redistricting Data at the census block level. Because blocks are the smallest geographic units the Census offers, we can match them to your chosen areas with a high degree of precision—even if a district or boundary is oddly shaped.

• Adjusted for Redistricting: Individuals counted in state prison facilities are reassigned to their last known residential address (per California Elections Code §21003).
• Rich Detail: Since we’re working from the block level, population counts for race and ethnicity line up closely with every corner of the map.

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Socioeconomic Data (2019–2023 ACS)

For metrics like income distribution, rent costs, or how many residents have a bachelor’s degree, we turn to the 2019–2023 American Community Survey 5-Year Data . The ACS provides updated estimates every year by surveying a sample of households. Because it uses somewhat larger units (like census tracts or block groups), we may blend data if a tract crosses multiple boundaries.

Direct vs. Estimated Alignment: Our data for counties, cities, legislative districts, and full school districts lines up directly with the ACS files, since those boundaries match exactly. But for smaller or custom borders—like city council districts, school board trustee areas, or a county supervisor’s district—we weight each tract or block group based on how much it overlaps with that particular area. This process still provides a reasonable reflection of local conditions, yet it’s worth keeping in mind that the ACS is survey-based and not an exact headcount.

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Why These Numbers Matter

Combined, the precise block-level population counts and the wide-ranging ACS survey data give you a broad yet nuanced look at California’s diverse communities. Here’s a quick overview of what you can learn:

• Population & Demographics: See how many people live in a particular area and how they identify by race or ethnicity.
• Income Distribution: Explore the share of households in different income brackets (e.g., under $35K vs. over $100K).
• Housing Insights: Check out homeownership rates, median rent, or how many residents are severely rent-burdened (spending more than half their income on housing).
• Education & Work: Identify how many people hold higher degrees, are in the workforce, or work from home.

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Interpreting “High,” “Average,” “Low,” and More

You might notice some metrics labeled “very low”, “low”, “average”, “high”, or “very high”. These labels reflect how a particular value stacks up within its own group of similar places—counties are compared against other counties, cities against cities, and so on. We take all the jurisdictions in that group, line up their values from smallest to largest, and then divide them into five ranges:

• Very Low: Among the bottom 20% of that group (e.g., counties with the lowest median income).
• Low: Falls above “very low” but still below the median, typically in the 20th to 40th percentile.
• Average: Near the middle 20%, suggesting it’s neither especially high nor low compared to its peers.
• High: In the upper 20% to 40% slice, meaning it outranks the majority of similar places but isn’t at the very top.
• Very High: Among the top 20%, indicating one of the highest values within that group.

This method provides a quick way to see if an area’s number is on the lower side, roughly in the middle, or closer to the upper end—always relative to similar types of jurisdictions.

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Updates & Future Releases

The 2020 population data will likely remain stable for redistricting purposes until the next decennial count, but we’ll periodically refresh our ACS numbers if new estimates come out. Since our site is still evolving, exact timelines may vary—but you can expect updates whenever significant changes are released.

By combining official, block-level population counts with flexible, survey-based ACS data, we aim to offer a robust and engaging look at the many facets of life across California’s communities.