Categories of Data in the Table Rows

Column Categories

Below Poverty Line (100 Percent and 125 Percent)--Low income classifications to which certain households are assigned. "Below 100 percent of poverty line includes households with incomes below the poverty level as defined by the U.S. Bureau of the Census and the Office of Management and Budget. "Below 125 percent of poverty" includes households with incomes below 125 percent of the poverty level. These groups of the poor and near-poor represent alternative levels for defining poverty. The poverty line varies with the number of family members in the household and the income of the entire family. (See Eligible for Federal Assistance below.)

Census Region--Four regions as defined by the U.S. Bureau of Census. For a map showing the four Census regions (and nine Census divisions), see Appendix E. For a listing of the States included in each Census region (and division), see the Glossary.

Climate Zone--One of five climatically distinct areas, defined by long-term weather conditions affecting the heating and cooling loads in buildings. The zones were developed by the Energy End Use and Integrated Statistics Division (EEUISD) from seven distinct climate categories originally identified by the American Institute of Architects (AIA) for the U.S. Department of Energy and the U.S. Department of Housing and Urban Development. The zones were determined according to the 30-year average (1961-1990) of the annual heating and cooling degree-days (base 65 degrees Fahrenheit). For additional details, see the Glossary.

Cooled Floorspace--Computed as heated floorspace times the percentage of rooms that are cooled over total rooms. If the housing unit has no heated floorspace then total floorspace is substituted for heated floorspace in the computation of cooled floorspace.

Cooling Degree-Days (CDD)--A measure of how hot a location was over a period of time, relative to a base temperature. In this report, the base temperature is 65 degrees Fahrenheit, and the period of time is 1 year. The cooing degree-days for a single day is the difference between that day’s average temperature (the mean of the maximum and minimum temperature for a 24-hour period) and the base temperature if the daily average is greater than the base; it is zero if the daily average temperature is less than or equal to the base temperature.

Eligible for Federal Assistance--Households are categorized as eligible for federal energy assistance if their income is below the federal maximum standard. The Federal standard is 150 percent of the poverty line or 60 percent of statewide median income, whichever is the higher income. Individual States can set the standard at a lower level than the federal maximum. (See Below Poverty Line above.)

Family Income--The total combined income (before taxes and deductions) of all members of the family from all sources, for the 12 months prior to the interview. This definition includes the total income of all family members who lived in the household during the 12 months prior to the interview, regardless of whether they were living there at the time of the interview. For additional details, see Family Income Category in the Glossary.

Floorspace (square feet)--The floor area of the housing unit that is enclosed from the weather. Basements are included, whether or not they contain finished space. The finished space and the heated space in attics are included. Garages are included if they share a wall with the house. Crawl spaces, even if they are enclosed from the weather, are not included. Sheds and other buildings that are not attached to the house are not included.

Heated Floorspace--The portion of floorspace that is heated during most of the winter season. Rooms that are shut off during the heating season to save fuel are not counted as heated square footage. Attached garages that are unheated and unheated areas in basements and attics are not counted as heated floorspace.

Lights Used One or More Hours per Day--All the light bulbs controlled by one switch are counted as one light. For example, a chandelier with multiple lights controlled by one switch is counted as one light. A floor lamp with two separate bulbs controlled by two separate switches would be counted as two lights. Indoor and outdoor lights were counted only if they were under the control of the householder.

"Incandescent Lights" are the most common household lamps. Electricity runs through a tungsten filament that glows and produces a soft, warm light. Because so much of the energy used is lost as heat, these are highly inefficient sources of light. These common general-service bulbs emit light in all directions.

"Fluorescent Lights" are usually long, narrow, white tubes connected to a fixture at both ends of the lamp; some are circular tubes. The inner surface of the tube is coated with a material that fluoresces (emits visible light) when bombarded with secondary radiation generated by a gaseous discharge within the tube. These lights are typically found in kitchen and basement work areas. Newer types ("compact" fluorescent lamps), looking somewhat more like a conventional incandescent bulb, are being made, which can be screwed into fixtures.

Type and Ownership of Housing Unit--"Single-Family Housing Unit" is a unit that provides living space for one household or family. The structure may be detached or attached to another unit. Attached houses are considered single-family houses as long as the house itself is not divided into more than one housing unit and has an independent outside entrance. A single-family house is contained within walls that go from the basement or the ground floor (if there is no basement) to the roof. (A mobile home with one or more rooms added is classified as a single-family home.) Townhouses, rowhouses, and duplexes are considered single-family attached housing units, as long as there is no household living above another one within the walls that go from the basement to the roof to separate the units.

"Multifamily (two to four units)" is a housing unit in a building with two to four housing units--a structure that is divided into living quarters for two, three, or four families or households and in which one household lives above another. This category also includes houses originally intended for occupancy by one family (or for some other use) that have been converted into separate dwellings for two to four families. Typical arrangements in these types of living quarters are separate apartments downstairs and upstairs or one apartment on each of three or four floors.

"Multifamily (five or more units)" is a housing unit in a building with five or more housing units--a structure that is divided into living quarters for five or more families or households and in which one household lives above another.

"Mobile Home" is a housing unit built on a movable chassis and moved to the site. It may be placed on a permanent or temporary foundation and may contain one or more rooms. If rooms are added to the structure, it is considered a single-family housing unit. A manufactured house assembled on site is a single-family housing unit, not a mobile home.

"Owned/Rented" describes the relationship of a housing unit’s occupants to the structure itself, not the land on which the structure is sited. "Owned" means the owner or co-owner is a member of the household and the housing unit is either fully paid for or mortgaged. A household is classified "rented" even if the rent is paid by someone not living in the unit. "Rent-free" means the unit is not owned and no money is paid or contracted for rent. Such units are usually provided in exchange for services rendered or as an allowance or favor from a relative or friend not living in the unit. Unless shown separately, rent-free households are grouped with rented households.

Year of Construction--The year the structure was originally completed or the year any part of the structure was first occupied. For mobile homes, year of construction is the model year.