Zip Code Radius Calculations with Microsoft Excel
Microsoft Excel “custom functions” can be used to perform many tasks related to address and location-based information, such as importing demographic data, verifying address accuracy, even calculating driving time, and performing route optimization. Custom functions, also called user-defined functions (UDFs), perform complex tasks or calculations and are used in cell formulas just like standard Excel functions, such as SUM or AVERAGE. In this article, we’ll discuss how custom functions can also be used to identify postal codes within a specific distance, or “radius”.
Zip codes can be extremely useful for analyzing demographic information and can help you better target customers and plan marketing campaigns. For example, identifying ZIP codes within a specific radius of potential new store locations can help you select a more accessible location for your customer base. But instead of drawing circles on a map, a much easier approach is to use a custom function within Excel that can do the work for you.
Let’s say you’re evaluating a potential store location in the 07470 ZIP code and need a list of all ZIP codes within a 10-mile radius. To use a function called RADIUS, simply enter a formula in a worksheet cell like this: “=RADIUS(ZipCode, RadiusDistance)”. For this case, the formula is “= RADIUS(“07470″, 10)”, and the worksheet will display all results within 10 miles of 07470.
The formula can be adapted to output the data as a text string enumerated in a single cell, or as an array with individual results in multiple spreadsheet cells. To return a formula as an array in Excel, simply highlight the target range with your mouse, then hold down the Ctrl and Shift keys and press Enter. The returned data can also include the calculated distance and order it by closeness to the destination zip. Additional options can be added to return the distance in kilometers or miles.
The custom function automates the process of finding all zippers that fall within the given radius by searching a local database and performing distance calculations based on latitude and longitude. All of these actions happen in the background, so the user works entirely in Excel and only sees the resulting list of postal codes displayed on their worksheet; there is no need to learn a new application or import a list of zip codes from a web page.
A big advantage of custom functions is their ability to process large amounts of data in spreadsheet format. To perform ZIP code radius calculations for a list of ZIP codes in column A, for example, simply enter the appropriate custom function formula in cell B1, such as: “=RADUS(A1, 10)” where “A1” is the worksheet cell location of the first zip code. Then just copy and paste this formula as needed in column B; In this way, you can perform radius calculations for literally thousands of ZIP codes, without time-consuming manual entry for other programs.
There are other useful Excel custom functions that complement these radius calculations, such as calculating the distance between two given postal codes. The custom function formula in this case would be something like “=DISTANCE(ZipCode1,ZipCode2)”. The calculated distance can be “as the crow flies” or it can be an estimate of actual driving distance or time.
A radio custom function is a great example that shows how Microsoft Excel functions can be used to automate complicated tasks, all within a simple spreadsheet formula. From calculating driving distance and time between addresses to identifying zippers within a specific radius, custom functions are a very useful approach to analyzing address and location-based information in Excel.
