Census confidentiality protections—what we call “disclosure avoidance”—have evolved over time to keep pace with emerging threats. Since the 1990 Census we’ve added “noise”—or variations from the actual count—to the collected data. For 2020 Census data we’re applying noise using a newer protection framework based on “differential privacy.” Learn more here about why and how we’re modernizing our protections and how you can engage in the process.
For an overview, read this brief: Why the Census Bureau Chose Differential Privacy