Income – Income and AMI
This indicator reports the percentage of households at various income levels relative to Area Median Income (AMI) of total households.
Source
Source Description
The American Community Survey (ACS) is a nationwide survey designed to provide communities with reliable and timely social, economic, housing, and demographic data every year. The ACS has an annual sample size of about 3.5 million addresses, with survey information collected nearly every day of the year. Data are pooled across a calendar year to produce estimates for that year. As a result, ACS estimates reflect data that have been collected over a period of time rather than for a single point in time as in the decennial census, which is conducted every 10 years and provides population counts as of April 1. The Census Bureau combines 5 consecutive years of ACS data to produce estimates for geographic areas with fewer than 65,000 residents. These 5-year estimates represent data collected over a period of 60 months. Because the ACS is based on a sample, rather than all housing units and people, ACS estimates have a degree of uncertainty associated with them, called sampling error. In general, the larger the sample, the smaller the level of sampling error. Data users should be careful in drawing conclusions about small differences between two ACS estimates because they may not be statistically different.
For more information about this source, including data collection methodology and definitions, refer to the American Community Survey data user’s website.
Methodology
This indicator reports the number of households at different income levels. Income levels are based on percentages of Area Median Income (AMI). To generate this data, AMI is acquired for each county using data from the 2018-2023 American Community Survey (ACS). Income levels at set percentages of AMI are calculated for each county. For example, the AMI for Washington, DC is $64,267. In DC, a family earning 40% of AMI earns $22,494 per year.
Using these thresholds, the number of households earning at-or-below each income level is estimated using ACS data on household income*. In the ACS, these data are presented in the form of counts of units with income that falls in certain ranges. For example, in Washington, DC there are 11,975 households with income between $10,000 and $15,000. To determine the number of households earning at-or-below AMI, a proportional allocation method is used. Using the example above, the total number of households earning up to $22,494 is calculated as follows:
Units with income <$22,494 =
[# INC $0 – $10,000] +
[# INC $10,000 – $15,000] +
[# INC $15,000 – $20,000] +
[# INC $20,000 – $25,000] * [(25000 – 22494) / 5000]
Thus all units with income (INC) in the ranges 0-10K, 10K-16K, and 16K-20K are counted, and around 50% of those units in the 20K-25K range. Using this method, the data shows that there are approximately 53,878 units available to families earning up to 40% of AMI in Washington, DC.
For more information on the data reported in the American Community Survey, please see the complete American Community Survey 2023 Subject Definitions.
Data Breakouts Available
- Owner-Occupied Household Income and AMI, Percent by Income Level
- Owner-Occupied Household Income and AMI, Percent of Total Households
- Renter-Occupied Household Income and AMI, Percent by Income Level
- Renter-Occupied Household Income and AMI, Percent of Total Households