Show Block Group Boundaries Yes No
Show Block Group Boundaries Yes No
Auto ownership costs, for the purposes of this research, have been defined as the cost of depreciation, finance charges, insurance, license, registration and taxes (state fees) per auto. These costs are largely fixed, less determined by use, and therefore, a result of simply owning an automobile.
Auto use costs, for the purposes of this research, have been defined as the cost of gas, maintenance and repairs per mile. These costs are largely variable and therefore determined primarily based on the level of use of the automobile.
Calculated in acres, Average Block Size is the average size of all the blocks making up a given block group. It is determined by dividing the total land area in a block group by the number of blocks in the block group.
Household Income includes the income of the householder and all other individuals 15 years old and over in the household, whether they are related to the householder or not. This value represents the aggregate household income divided by the count of households composing the aggregate at the block group level.
Average Household Size reflects the value, at the block group level, of total population in occupied housing units divided by the count of occupied housing units.
Average Monthly Ownership Costs represent the monthly costs for housing considering only owner-occupied housing units with a mortgage. Average Monthly Ownership Costs are calculated using the US Census variable of Selected Monthly Owner Costs.
Average Monthly Rent represents the monthly costs for housing considering only renter-occupied housing units paying cash rent. Average Monthly Rent is calculated using the US Census variable of Gross Rent.
Average Regional Gas Prices were obtained for the year 2000 from the U.S. Energy Information Administration (http://www.eia.doe.gov).
A subdivision of a census tract, a Block Group is the smallest geographic unit for which the Census Bureau tabulates sample data. All data utilized in the H+T Index, unless otherwise noted, are calculated and modeled at the block group level.
Carbon dioxide is generated as a by-product of the combustion of fossil fuels or the burning of vegetable matter, among other chemical processes. Here, we refer to the CO2 emissions resulting from private automobile use.
Commuters per Household is defined as all workers not working at home per household. The count of total workers has been scaled by the ratio of population in households to group quarters to account for workers not living in households.
A Cost Burden represents an expenditure as a percent of income.
Employment Access Index is a weighted measure developed by CNT to estimate both the quantity of and residents’ access to the jobs in a region. It is calculated using an inverse-square law to model total access to jobs in the metropolitan area by using the sum of the number of jobs divided by the square of the distance to those jobs.
FTA is one of 11 operating administrations within the U.S. Department of Transportation. FTA provides stewardship of combined formula and discretionary programs to support a variety of locally planned, constructed, and operated public transportation systems throughout the U.S. (http//www.fta.dot.gov).
Frequency of Service represents an estimate of the number of times a given transit route runs in a given amount of time. For this research, frequency of service has been estimated from either headway data provided by the transit agency or directly from route schedules. Route frequency is estimated as trips per week.
In reference to automobiles, an average fuel efficiency figure of 20.3 mpg has been utilized.
Gasoline Expenses refer to the amount of money spent by a household on gasoline in a given period of time. These values are calculated using modeled vehicle miles traveled per household, reported gasoline prices, and an average fuel efficiency of 20.3 miles per gallon.
Housing Costs represent the average cost of housing for a given block group. Here, housing costs are calculated as an average of Selected Monthly Owner Costs and Gross Rent factoring the percentages of owner occupied housing units with a mortgage and renter occupied housing units with cash rent obtained from the US Census.
Household Income includes the income of the householder and all other individuals 15 years old and over in the household, whether they are related to the householder or not. This value represents the median at the block group level.
A Metric Ton is a common international measurement for the quantity of greenhouse gas emissions. A metric ton is equal to 2205 lbs or 1.1 short tons.
A geographic entity defined by the federal Office of Management and Budget for use by federal statistical agencies, based on the concept of a core area with a large population nucleus, plus adjacent communities having a high degree of economic and social integration with that core. Qualification of an MSA requires the presence of a city with 50,000 or more inhabitants, or the presence of an Urbanized Area (UA) and a total population of at least 100,000 (75,000 in New England). (http://www.census.gov)
Public Transit Costs represent the average household costs of transit at the block group level. These costs are based on figures obtained from the National Transit Database allocated based on transit use.
As defined in the Federal Transit Act, Public Transportation is "transportation by a conveyance that provides regular and continuing general or special transportation to the public, but does not include school bus, charter, or intercity bus transportation or intercity passenger rail transportation." (http://www.ntdprogram.gov/ntdprogram/Glossary.htm#P)
Regions are defined as the federal Office of Management and Budget (OMB) metropolitan areas as utilized in the 2000 US Census. For this research, metropolitan statistical areas (MSAs) and primary metropolitan statistical areas (PMSAs) were utilized.
Regional Peak Prices for gasoline were determined using prices from July 2008 as obtained from the U.S. Energy Information Administration (http://www.eia.doe.gov/).
Three primary income levels have been used to represent typical households in this research. The Regional Typical Household uses the Regional Median Household. The Regional Moderate Household uses 80% of the Regional Median Household Income. The National Typical Household uses a value of $41,994, or the National Median Household Income. By fixing income levels, both as model inputs and in cost burden calculations, this research controls for variation resulting from household income and other household characteristics. Therefore, variation seen in modeled transportation costs can be interpreted as resulting from the built environment, or neighborhood characteristics alone.
Residential Acres are defined as the land area of all blocks in which gross density (households per land acre) is greater than one.
Residential Density represents household density of residential areas, in contrast to population density on land area. Blocks (within block groups) are selected on the criteria that gross density (households per land acre) must be greater than one. From these selected blocks, both households and land acres are aggregated to the block group level, at which level residential density is calculated as households per residential acre.
The Transit Access Index (TAI) was developed by CNT as a measure of transit availability. The TAI is based on the number of bus routes and train stations within walking distance for households in a given Block Group. The TAI does not include the frequency of service. This measure is not available to all metro areas because of data acquisition issues.
The Transit Connectivity Index (TCI) was developed by CNT as a measure of transit service levels. The TCI is based on the number of bus routes and train stations within walking distance for households in a given Block Group scaled by the frequency of service. This measure is not available to all metro areas because of data acquisition issues.
Transportation Costs represent the total cost of household transportation. Here, transportation costs are defined as the sum of auto ownership costs, auto use costs, and public transit costs.
Travel Time to Work, calculated in minutes, refers to the total commute time. From the US Census, this value represents the time it usually takes a person to get from home to work each day. The elapsed time includes time spent waiting for public transportation, picking up passengers in carpools, and time spent in other activities related to getting to work.
Three Typical Households have been considered. The Regional Typical Household assumes a household income of the median income for the region, the average household size for the region, and the average commuters per household for the region. The Regional Moderate Household assumes a household income of 80% of the regional median, the regional average household size, and the regional average commuters per household. The National Typical Household assumes a household income of $41,994, the national median household income, a national average household size of 2.59, and a national average number of commuters per household of 1.14.
The transportation cost model has been developed to estimate the average costs of transportation at a neighborhood level, and in doing so, illustrate geographic trends and variation that exist. While household characteristics, such as income, play some role in determining a household's transportation costs, this research is intended to focus on the significant variation resulting from the built environment, or the efficiency of location. Therefore, CNT controls for household variation by establishing Typical Households with fixed values for household income, size and commuters per household.
Vehicle Miles Traveled represents the average annual auto travel by households. This includes commute travel, but also all other daily auto trips.
The H+T Affordability Index home page has a map of the United States with all 337 metropolitan areas displayed in different colors. To select a region, use the cursor icon to zoom and then click on the desired metropolitan area. You can also use the hand icon to hover over different boundaries to identify regions. Once you click on a metro area, the H+T maps will load directly.
To view a different region, click on the arrow labeled "Region."
A map will appear. From here, you can select a new region in one of three ways. You can select from the drop down box using the down arrow to the left of the box or you can type in the name of the metro area. You can also click the region you wish to view on the map of the United States.
Each map has a legend above it with the name of the variable that is being depicted. For example, "Transportation Costs, % Income" under the Affordability Indices subheading or "Autos per Household" under the Household Model Outputs subheading.
To change this variable, click on the arrow labeled "Change."
A list of variables will appear, each with two circles to the left of it. Click on two circles; one for the variable you wish to see on the left map, and one for the variable you wish to see on the right map. If you do not know what a variable is, hover over it, and a description will appear. The list of variables will automatically close after you select two to view, or if you only want to change one map click on it and then exit the menu by clicking the grey "X" in the upper right corner of this menu.
Every left map has a set of tools to help you zoom and pan. Use the arrow tool to center the map; then use the + and - signs to zoom in or out. You can also pan within the map by clicking within the map window and, while holding down the mouse, drag the cursor in any direction. The map can also be re centered by double clicking within the map window. Note that only the left map has these tools. The right map will automatically adjust to match the zoom of the map on the left.
These 4 tabs enable you to view preselected map comparisons for the 4 main themes presented in the H+T Affordability Index.
The H+T Index preselected map comparison shows Housing Costs as 30% Percent of Income compared to Housing and Transportation Costs as 45% Percent of Income.
The Gas Cost Impacts preselected map comparison shows Annual Household Gasoline Expenditures comparing 2000 to 2008.
The Greenhouse Gas Impacts preselected map comparison shows Carbon Dioxide Emissions from Household Auto Use, with the left map showing Emissions per Acre and the right map showing Emissions per Household.
The Custom Comparison option allows you to pick any two variables that you'd like to see compared. For example, how does Household Density compare to Transportation Expenditures? Are Carbon Dioxide Emissions lower where the Transit Connectivity Index is higher?
These Legend options provide details about each map shown. The first legend provides the most basic descriptive information, and the last presents the most detailed and technical information.
Legend and Description:
This is a traditional map legend showing the value ranges represented by the colors on the map as well as providing a description of the given variable.
Summary Table of Statistics:
The summary table of statistics shows statistics for both the viewable area on the map as well as for the whole region. Statistics shown include the count of Census block groups, the minimum value of the variable, the average value, the maximum value, and the total count of households. Note that if you zoom in or out on the map, the values in the Viewable Area on Map Below column will change to reflect the new map view. However, the values for the Region will remain the same.
Graphical Legend:
The graphical legend shows the count of block groups in each color/value range. Note that if you zoom in or out on the map, these bar charts will change to reflect the new map view.
Histogram Legend:
The histogram legend shows a bar chart representing the frequency distribution of the count of block groups for each value of the given variable, with the range showing the 5th to 95th percentiles. Note that if you zoom in our out on the map, the histogram will change to reflect the new map view.
Line-Graph Showing Correlation to H, T, and H+T:
This legend shows graphs comparing the given variable with Housing Costs, Transportation Costs, and Housing + Transportation Costs, all as percents of income. Note that if you zoom in our out on the map, these graphs will change to reflect the new map view.
Household Income, Household Size, and Workers per Household all represent values for the Region. One important detail of the H+T Affordability Index is that transportation costs are calculated for the "average" household in the region, or the household represented by these three values. By doing this, impacts of these variables on transportation costs are controlled for, and differences in costs resulting from neighborhood characteristic are highlighted. When values are shown as percents of income, this income value is used. Therefore, the values can be interpreted as the cost impact of a given location on the average household in the region.
When you change variables, the Compare menu box pops up where you can chose a theme for the left map and a theme for the right map. At the top of this menu box are three household types that can also be changed. Note that transportation costs are calculated for a typical household using three main household characteristics; median income, household size and average working commuters per household.
The Regional Typical Household is the default household and is based on the average household living in that particular metropolitan area. The Area Median Income (AMI) is based on the Census-defined median income for the whole metro area, Average Household Size and Average Working Commuters per Household are also based on Census Information. By using these three variables, the model can control for the impact these three variables have on transportation costs. The Regional Typical Household allows the user to see which areas of the selected metropolitan area are affordable to that region's average resident.
The Regional Moderate Household is used to represent a working family in the selected metropolitan area. Income is based on 80 percent of the area median income (AMI) where average household size and average working commuters per household remain constant for the regional average. This household type allows the user to view areas that are affordable to the typical working family, who might have a more constrained household budget.
The National Typical Household models affordability based on the typical national household as defined by the 2000 Decennial Census. The Area Median Income (AMI) is $41,994 per household, the average household size is 2.59 and the average working commuters per household is 1.14. While AMI, household size and number of commuters in a household varies between metropolitan areas, the National Typical Household allows the user to see how affordability changes when income and household size and number of commuters are held constant.
You can click on any block group in the map window and a small window will display the values behind the thematic map. In the map below, transportation cost as a percent of income is displayed. The user can see the actual percent value for the block group that was clicked as well as how it compares to the city or municipality average, county average and lastly, the average for the entire metropolitan area.
There are two ways for the user to zoom to the selected block group. You can click on the blue text link that says "Blockgroup" or you can click on the blue Zoom to Block Group link and the map will zoom into the closest level for the viewer to see the block group that was originally clicked. The map will center on the block group that was selected.
At this zoom level, green block group boundaries will automatically turn on so that the user may differentiate between neighboring blocks, particularly when neighboring block groups have similar color variation. Block group boundaries can be turned off by clicking the toggle button "No" next to Show Block Group Boundaries in the box in the upper right hand corner.
Yes, click on the legend button that is second from the left on the legend option bar. When your mouse hovers over this legend option a yellow bubble will read View Summary Table of Statistics.
You will notice in the summary table of statistics that some values are in green text and others are in blue text. Values that are in blue are enabled with a zoom feature. In the example below, the minimum Housing and Transportation Costs as a Percent of Income in the region identified is 20%. If you click on the 20% value, a legend bubble will appear on the map window asking you if you would like to zoom to the block group with that 20% value. Click on the Zoom to Blockgroup text in the pop up and you will automatically be redirected to that block group. This feature is available on all variables the minimum, average, and maximum values.
Yes, click on the Share button.
The following screen will appear. You have several options to share your link:
There are five links on the upper right hand site of the website heading. If you click on the second link, "About," you will be directed to a summary of the H+T Affordability Index's background.
There is a menu on the right side of the page that lists a number of reports and community profiles. Penny Wise, Pound Fuelish is the report that accompanies the most current release of the Housing + Transportation website. There are also three H+T Metro Reports which are customized reports produced by CNT as a consultant for certain cities and regions. The H+T Community Profiles summarize H+T results in selected metropolitan areas along with a summary of the national level results.
Start with the glossary. The link is the fourth one from the left on the menu bar.
The glossary window will pop up and define all the variables used in the model and all terms used on the website.
Yes, next to the Glossary link on the menu bar is a link that says "Subscribe to mailing list."
Click on this link and the following box will appear:
Please fill out your name and email and CNT will be happy to keep you posted on any updates and H+T news.
Select the region that you are interested in. The default maps are housing costs as a percentage of income, and housing and transportation costs as a percentage of income. "Legend and Description" is the default display; click on the arrow labeled "Change" to bring up the Display menu.
Three of the displays: "Population Statistics," "Household Statistics," and "Neighborhood Statistics" provide information applicable to the HUD NOFAs. Select "Population Statistics."
The legend changes and now indicates the number and percentage of people in block groups where costs meet or exceed affordability standards, including where housing and transportation costs are 45% and greater.
The population statistics are given for the area visible on the map, but the area of focus can be changed. When you zoom or pan to change the map view the statistics will update. You can also click on the "Focus" dropdown menu to obtain population statistics for areas other than the map area.
"Whole Region" provides data for the entire region while "County" and "Municipality" allow you to view data for any county or municipality within the region. Select "County" (the following steps are also applicable for "Municipality") to bring up another dropdown menu with a list of all the counties in the region.
After you choose a county the population statistics will update and the map will zoom to your selection, with the boundaries of the county highlighted.
To determine the number of households that spend more than 45% of income on housing and transportation costs, click the "Change" arrow again to bring up the Display menu and choose "Household Statistics."
The area of focus will remain the same, but you can follow the same steps as you did with "Population Statistics" to change it. "Neighborhood Statistics" gives data on the proportion of neighborhoods (Census block groups) that are affordable or unaffordable.
