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GeoMetrx Common Ground News: Volume 1: Issue 10 – ZIP Codes: Then and Now

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Volume I : Issue 10

October 2012

Welcome to Common Ground News

In this issue:

* Feature Article – ZIP Codes: Then and Now

* Tips & Techniques – helping you get the most out of our online mapping
application at [1]GeoMetrx “Creating Territory Reports: a video tutorial”

* Thematic Map – ZIP Code Overlays – understanding the difference between
boundaries, polygons and points; plus how to research valid and invalid ZIP

* Trivia Challenge​​ – Average ZIP Code Populationl

This and all our future newsletters are available through our Knowledge Center
resource listed on our website. We encourage you to share our Common Ground
News with your friends and colleagues and we welcome your feedback. Visit our
website and make a comment on the [2]contact us page or send us an email at

—-Kent Hargesheimer,

Managing Partner


Phone: 1.888.848.4436

Web: [4]





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Blog: [14]Common Ground Blog

Newsletter Archives:
• [15]September 2012
• [16]August 2012
• [17]July 2012
• [18]Previous Issues

ZIP Codes: Then and Now


ZIP Codes, those handy little five digits (okay, sometimes nine… ZIP+4) are
something we use regularly, yet probably don’t think much about. They’ve existed
since the beginning of time, right? Or at least since the inception of the
Postal Service (USPS), right? Wrong! In fact, they have only been in existence
for about 50 years. Since then, their use has reached far beyond the intention
of their initial purpose, which was simply to improve the efficiency of mail
delivery, but more on that in a bit.

The Zone Improvement Plan – ZIP Code system – has roots that reach back to WWII.
In 1943, the Postal Service implemented postal zones for large cities as a way
of making mail sorting easier for the new and inexperienced postal clerks who
were filling in for those who had gone into military service. Cities were
assigned a two-digit code. For example:

• Rochester, NY – 11

• Minneapolis, MN – 16

• Boston, MA – 24

• Los Angeles, CA – 54

This system remained in place until July 1, 1963, when the current ZIP Code
system was implemented. The country was divided into ten geographical regions
(groups of states), and the first digit of the codes designated the area: zero
in the Northeast all the way to nine in the West. The second and third digits,
combined with the first, identify a sectional center facility (SCF), which is a
postal facility that serves as a processing and distribution center for an area.
In most cases there is one SCF for every unique 3-digit ZIP Code range, although
some SCFs cover several. The fourth and fifth numbers identify a much more
specific area whether a district, city, town, village or a smaller area within
these. There are currently over 42,000 ZIP Codes in use today.

Within a 3-digit ZIP Code region, the main town or city is typically assigned
the first, or lowest, ZIP Codes in the region, with subsequent towns being
assigned ZIP Codes in alphabetical order; which would explain why ZIP Code
numbers often are not numerically adjacent to one another. ZIP Codes were
introduced to streamline mail delivery only, and there are some exceptions to
ZIP Code assignments based on the confines of geographical features and mail
delivery routes. Therefore, ZIP Codes cannot be used to pinpoint exact
locations, such as can be done with the lat/long system used in mapping and GIS
technology. One such anomaly, for example, is 00501 which is assigned to the
IRS center in Holtsville, NY; most other NY ZIP Codes begin with 1.

There are four types of ZIP Codes: Unique; P.O. Box; Military; and Standard.
Unique ZIP Codes are assigned to a high volume address including government
agencies, universities and even some businesses such as 12345 for General
Electric in Schenectady, NY (note: thousands of children send letters to this
ZIP Code each year that are addressed to Santa Claus, because it’s the most
logical ZIP Code for the North Pole, of course!). P.O. Boxes, which are located
at post offices around the country are assigned a ZIP Code that is only used for
those P.O. Boxes. Military ZIP Codes are assigned to a US Military Institution
APO/FPO/DPO. The remainder of ZIP Codes are Standard, which are the most common
and assigned to home and business addresses in the areas surrounding SCFs and
other Post Office facilities.

During the 1960s and 70s, the USPS heavily promoted the usage of the new ZIP
Codes, and even utilized a cartoon character mascot, Mr. ZIP, to encourage the
adoption of the system by everyone. Ironically, the only time the USPS ever
issued a stamp promoting the use of ZIP Codes, they didn’t utilize Mr. ZIP,
though he was often depicted on the covers of stamp booklets, and in the selvage
portion of stamp panes. Use of ZIP Codes was not required at first, however,
beginning in 1967, mailers were required to pre-sort second and third-class bulk
mail by ZIP Code.

Today ZIP Codes are required on:

• Express Mail

• Commercial First-Class Mail

• First-Class Package Service

• Periodicals

• Standard Mail

• Package Services and Parcel Select

• U.S. Military Addresses

• APO and FPO Addresses

• Official Mail

• Business Reply Mail

• Merchandise Return Service Mail

The only mail not required to have ZIP Codes is single-piece First-Class mail,
Priority Mail, single-piece Parcel Post, and pieces with a simplified address
(i.e. addressed to “Postal Customer” or other generic recipient) that do not
fall in a category listed above.

In 1983, the system was expanded one more time with the introduction of the ZIP
+ 4 codes, which use the basic five-digit codes, plus four more digits to
further segment geographic areas such as city blocks, apartment complexes, and
in some cases individuals, such as a particular business, that receive
high-volumes of mail, but do not have their own Unique ZIP Code. The ZIP + 4 is
not mandatory except for certain presorted mailings. In a further effort to
provide even more specific delivery point information, the USPS, through the use
of sophisticated optical readers, applies an 11 digit Postnet barcode to most
mail pieces, greatly increasing the speed and accuracy of mail delivery.

Image Courtesy of [19]

ZIP Codes have become more than a string of numbers placed on an envelope to
speed up delivery. Though it was unintended, the use of ZIP Codes in sales and
marketing applications, internet technology, data collection and analysis, GIS
and more is far reaching. Delivery companies such as FedEx, UPS and others
require USPS ZIP Codes for routing their deliveries, rather than developing
their own segmentation systems. ZIP Codes are also used in online applications
such as locator software, which returns business and store location results and
distances calculated from the lat/long center-points of ZIP Codes.

However, the most prolific use of ZIP Codes outside of delivery and location
sourcing is marketing and data applications. The U.S. Census Bureau and many
other statistical collection agencies use ZIP Codes as a way of tracking and
amalgamating data. Direct mail campaigns use ZIP Codes to target potential
customers (“birds of a feather flock together”). Retail stores regularly collect
ZIP Codes as a way of determining the location of their customer base, and will
often use this data when selecting new sites. When used in combination with
credit card numbers, even more data can be collected by businesses. While many
of us hesitate to share our ZIP Code at point-of-sale transactions, doing so
enriches the data we use in our businesses to better serve our customers and to
develop sound business strategies. So don’t be selfish – share that ZIP!

Tips & Techniques –

Creating Territory Reports

Visualizing your territories is extremely valuable, and being able to combine
that with data output is exponentially even more useful. In our most recent
video tutorial, we show you how to create territory reports step by step.

Reports allow you to see the your data both visually and in table format
simultaneously. Once you have created your report you can either download the
information to a spreadsheet for analytical purposes or send it to other team
members directly via email. Reports can include information from any of the
variable data sets in [20]GeoMetrx including data you have uploaded.

[21]Click here to view the video.


ZIP Code Overlays: Boundaries, Polygons and Points


In [23]GeoMetrx there are three ZIP Code Overlay options: Boundaries; Polygon;
and Point.

– The Boundaries overlay provides exactly that, a visible boundary, or border,
around a polygon shape representing a STANDARD ZIP Code area, which is assigned
to a particular geographic area of homes and businesses.

– The Polygon Overlay adds the STANDARD ZIP Code Number to the map.

– The Point Overlay adds ZIP Code numbers to the map that are assigned to
either P.O. Boxes or UNIQUE addresses. UNIQUE addresses are ZIP Codes that have
been assigned to a single high-volume mail recipient such as a business,
university or government entity.

In the above example 75208 is a Standard ZIP Code assigned to all the homes and
businesses within the blue polygon boundary surrounding it, while 75285 and
75263 are assigned to a Unique entity and P.O. Box, respectively, and are
represented as points.

When uploading data to [24]GeoMetrx it’s important to understand the difference
between the polygon ZIP Codes and point ZIP Codes. If your dataset includes any
Unique or P.O. Box ZIP Codes, and you only select ZIP (Polygon) the software
will treat those codes as invalid. However, if you choose the ZIP (Point/Poly)
option when uploading all the ZIP Codes in your dataset will upload properly.

If you still bump up against and invalid ZIP Code when uploading data, it may
truly be invalid. Our [25]GeoMetrx ZIP Code database is updated regularly in
conjunction with USPS changes. The USPS regularly realigns ZIP Codes in an
effort to accommodate population growth and operational needs. The USPS
maintains an up-to-date online look-up tool which is the best resource to check
the validity of a ZIP Code. To access this resource
visit: [26] If you click the
“Cities by ZIP Code” tab, you can input individual ZIPs without also providing
an address. The look-up results are displayed immediately in the dialog window
as shown below:

For more information on how to obtain access to [27]GeoMetrx datasets, contact
us today at 1.888.848.4436.

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October 2012 – Trivia Challenge

1) What is the average population per ZIP Code according to the 2010 Census?

[28]Click here for the answers!