ZIP Code Database with Latitude and Longitude Greatly Improved with Census Demographics

March 4, 2013 - PRLog -- ZIP Code Databases with Latitude and Longitude have been used since the mid 1990’s in store locators in order to help people locate the nearest store. Over the years, the locators and the data used by them have improved somewhat, but today, GreatData.com, Inc. announces a giant leap in ZIP Code latitude and longitude accuracy.

The first vendor to provide this data over the Internet was GreatData.com. “In the early days, it was very difficult to have good latitude and longitude coordinates” says Paul Duggan, owner of GreatData.com. “We started out with the only file that we could find. It was from the U.S. government, so we thought that it must be correct. One of our first clients using this data had a weather site and called me to let me know that some ZIP Code’s latitude and longitude coordinates were in the Atlantic Ocean. We worked with them on cleaning up this data. It was difficult to do because the mapping tools weren’t too good back then.”

GreatData.com has come a long way since those early days. They realized that they couldn’t rely on government data and started manually verifying thousands of ZIP Code coordinates in order to ensure that they were not centered on waterways, in parks, golf courses, airports, etc. Duggan continued, “We wanted a population-based ZIP Code centroid [center point], not a physical centroid, so that the locator’s starting point would be near where most people lived. At the time, the best we could do was to manually verify each ZIP Code and assign the centroid based on the latitude and longitude of where the most densely populated area appeared to be. Since there are over 40,000 ZIP Codes, this was very challenging!”

Duggan elaborated further: “To better understand the problem, you would need to look at a ZIP Code such as 10023 in New York City. It’s an ‘L’ shaped ZIP Code with about 2/3rds of the ZIP Code covering Central Park. The physical center of the ZIP would be in Central Park. Our population-based centroid is accurately located where the people live.”

GreatData has employed many data verifiers over the years to ensure the most accurate data that can be available, knowing that standard, off-the shelf sources of data would never satisfy their very exacting Fortune 500 clients. They manually checked all the major metropolitan areas to get their latitude and longitude coordinates as accurate as possible.

“Recently, we’ve made some great strides into mapping (spatial) database products, particularly SQL Server with their spatial tools,” explained Duggan. “We’re always striving to improve our product, so using the latest technology is essential. We wanted to use Census population data to calculate the true population center of a ZIP Code. Through trial and error, including reviewing extremely sophisticated mathematical formulas, we have been able to develop a tool to greatly improve the accuracy of our ZIP Code latitude and longitude centroids. We’re now using that tool and will be rolling out ZIP Code / Latitude & Longitude improvements over the upcoming months!

“We’ve seen competitive products with a very high percentage of ZIP Codes off by miles, even over 20 miles off in densely populated areas! Clients that purchase the data don’t always know how to check the accuracy, and usually never hear from people who had trouble using their locator, so they assume all is well and keep using the same data. We invite prospective clients to test our data. Often they will ask for sample ZIP Code data in their local area. We have no problem providing them with custom sample files. The perfectionist is the client that we like! We know that they insist on only the best and we retain them for years.

“One client left us for a cheaper product. He used the data for an application which Apple purchased from him. When he told me that he wasn’t renewing with me he said, ‘Data is data, right?’ Later, Apple told him how displeased they were with the cheap data and he came back to us.”

GreatData.com has been in business over 20 years. They were the first company on the Internet to sell U.S. ZIP Code data, Canadian Postal Code data, Mexican Postal Code data, and many other products. They have procedures in place, refined over many years, to ensure the best data possible. Their specialties include U.S., Canadian and Mexican postal code databases, census demographics, Medicare CBSA codes, telephone area code / prefix data (NPANXX), Congressional Districts and Rural, Urban and Suburban designations for U.S. and Canadian postal codes. They invite prospective clients to compare their data to competitors. They can be found at http://GreatData.com.