How to calculate home price to income for a county: quick answers
Short, exact answers to the questions people ask before they build a home price to income figure from the County List with Demographics. Each one names the columns it uses. For the full spreadsheet walk-through, see the guide to reproducing our county affordability figures in Excel.
How do I calculate home price to income for a county?#
Divide a county's median home value by its median household income: median_home_value ÷ median_household_income. In a spreadsheet, with home value in column E and income in column D, it is =E2/D2, formatted as a number with one decimal place.
Which columns do I need, and what are they called?#
Two, and the names are exact: median_home_value and median_household_income. Add name to see which county each row is, and state_name to filter to one state. Type the column names as written when you reference them in a script or a lookup.
What does a worked example look like?#
Teton County, WY: 1,371,900 ÷ 112,681 = 12.175, or 12.2. Our Highest home price to income page reports it as "about 12", because the figure carries a margin of about ±2.0 years. Use the arithmetic as a check on your own sheet, and expect the page to show the rounded reading.
Why does our page say "years"?#
The result of dividing dollars by dollars has no unit. "Years" is a way of reading it: the median home value equals about 12 years of median household income in Teton County. It is a reading of the ratio, not a measured quantity.
Does a ratio of about 12 mean it takes 12 years to save for a home?#
No. It doesn't support that. A savings timeline would assume every dollar of household income goes toward the house, with nothing left for rent, food, taxes or anything else. Write it as a comparison of value to income, for example "median home value is about 12 times median household income in Teton County." Don't write it as a number of years to save.
What does median_home_value actually measure?#
The median value of owner-occupied homes in a county, from Census survey estimates. It describes homes that people live in and own. It is not a list of homes for sale, and it is not the price of a recent sale.
How exact is the figure? Can I say one county is higher than another?#
Both inputs are Census survey estimates, which carry a margin of error. Treat small gaps between two counties with caution, and don't report a few tenths of a point as a real difference. Don't report more than one decimal place. If a county has a blank in either column, it has no figure, so leave it out rather than treating the blank as zero.
Where do I get the file, and is there a step-by-step?#
The County List with Demographics is $199, one-time, as a UTF-8 CSV inside a .zip. The free sample shows the columns before you buy. For the steps from file to finished sheet, follow the Excel guide. To get every county, open the County List with Demographics.