MPO Policy and Procedures Manual - Indianapolis Metropolitan ...

Data
The primary data source for demographic data in the United States for over 60 years has been
the U.S. Decennial Census of the Population. This Census, performed by the U.S. Bureau of
the Census was last conducted in 2000 and contained two parts that year. The first part, called
the Short Form, was a 100% sample that provided population, household and voting data. The
Long Form, a sample of one in every six to eight households, provided detailed social,
economic and demographic information. Because of the sample size of the Long Form, this
detailed data set was available for small geographic areas.
In 2003, the Census Bureau initiated a new, annual survey called the American Community
Survey (ACS), to take the place of the detailed Long Form, beginning in 2010. The sample size
of the ACS is approximately one in every thirty-two households. Valid statistics for small area
statistics produced by the ACS are published as 5-year moving averages. The ACS began data
collection in 2005-2006 and its first 5-year estimates are due in 2010-11.
The MPO uses a special aggregation of Census data called the Census Transportation
Planning Package (CTPP), purchased on behalf of the transportation community by ASHTO
(the American Association of State of Highway Transportation Officials). The CTPP is
being modified to accommodate the change from the Census Long Form to the ACS. The MPO
also uses demographic data prepared by Nielsen-Claritas.
Economic data are garnered from a variety of sources. The MPO leases data from the D&B
Selectory data base and has acquired data from both the Indiana Secretary of State’s Business
Licensing data base and the Indiana Department of Workforce Development’s ES-202 data
base.
The MPO uses forecasts of economic and population values produced by both the State of
Indiana and Woods and Poole. These data are largely used as county- or township- level
control totals. These control totals are allocated to smaller geographic areas using a type of
land-use allocation model.
During 2008 and 2009, the MPO has conducted two significant travel data studies. The Central
Indiana Travel Survey (CITS) and the IndyGo On-Board Survey. The CITS collected data for up
to 4000 household upon its completion in December of 2009. The IndyGo On-Board Survey
collected data on over 4000 bus riders. Data from these two surveys will be used extensively in
updating the MPO’s travel demand model in 2010.
Transportation network data are garnered from a variety of sources, including the Indiana
Department of Transportation (INDOT), different local engineering departments, and original
data collection (both field and from aerial photography). Types of network data currently
collected include traffic counts, centerline locations, lane widths, facility types, and posted
speeds. During 2009, the MPO began full-time collection of traffic counts, finishing the third year
of a three-year system traffic count cycle.
Travel Demand Model Procedures
The travel demand model is a tool for estimating network volumes (vehicles per hour) and
speeds (miles per hour) thereby enabling the derivation of vehicle miles of travel (VMT) and
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