The air quality index is based on annual reports from the Environmental Protection Agency. Higher values are more favorable.

The average age of the residents.

The percentage of the area's population over the age of 25 with an associate's degree or other 2-year college degree.

The percentage of the area's population over the age of 25 with a bachelor's degree or other 4-year college degree.

The percentage of the population that commutes using public transportation.

The percentage of the population carpooling to work.

The percentage of the population driving to work in a single-occupant vehicle.

The projected change in job availability over the next ten years based on migration patterns, economic growth, and other factors. A projected decrease in available jobs is represented as a negative percentage.

An index, like the cost of living index, that compares health costs between areas. The average cost of health care in the U.S. is represented as a value of 100%. A value of 95% means it costs 5% less than the national average for healthcare in this geographic area, and a value of 110% means that it's 10% more expensive.

The percentage of the area's population over the age of 25 with high school diplomas or high school equivalency degrees (GEDs).

The percentage rate that home values have changed over the last year. Changes result from increased demand for housing or from an economic slowdown. Many times there is just a normal cycle of increasing home prices, followed by a correction, and more increases the next year. But steep or continued decreases are a cause for investigation.

The total number of households in the area, including homes and apartments.

The percentage of the area's population over the age of 25 with a master's degree, Ph.D. or other advanced college degree.

The total of all income taxes for an area, including state, county and local taxes. Federal income taxes are not included.

The ratio of male residents to females, which includes all ages.

The value in the middle when all ages are arranged from highest to lowest for the residents of a given geographic area. The median is considered by statisticians to be a better indicator than the average or mean because it is less skewed by high or low values.

The median age of homes, in years.

The value of the year's most recent home sales data (April 1999 to March 2000). It's important to note that this is not the average (or arithmetic mean). The median home price is the middle value when you arrange all the sales prices of homes from lowest to highest. This is a better indicator than the average, because the median is not changed as much by a few unusually high or low values.

The value in the middle when all incomes in a given geographic area are arranged from highest to lowest.

Median income for all residents of a geographic area who are employed. The median is the middle income, when all values are arranged from highest to lowest. The median is considered by statisticians to be a better indicator than the average or mean because it is less skewed by unusually high or low values.

The type of neighborhood (city, suburban, rural), based on its size, location and density.

The total of all the cost of living categories weighted subjectively as follows: housing (30%), food and groceries (15%), transportation (10%), utilities (6%), health care (7%), and miscellaneous expenses such as clothing, services, and entertainment (32%). State and local taxes are not included in any category.

The average number of members in a household, which consists of all the people who occupy a housing unit together.

The portion of the total population of the area that is female.

The portion of the total population of the area that is male.

The portion of the adult population of the area that is currently married.

Represents the proportion of the area's homes which are owned, compared to those which are rented. A high proportion of rented homes may indicate several things, such as expensive downtown apartments, student housing, or an area where the residents do not have the resources to become homeowners.

The portion of the adult (18 years and older) population of the area that is not currently married (includes never married, divorced, and widowed).

The number of medical and osteopathic physicians listed by the American Medical Association in a geographic area.

An estimated population based on the most recent U.S. census.

The number of residents per square mile.

Measures the likelihood of property crime in an area, based on the city and county crime rate, and social and demographic measures for the area. Property crime is a compilation of three crime categories: burglary, larceny and motor vehicle theft.

The percentage of increase or decrease in available jobs over the most recent 12-month period. A decrease in available jobs is represented as a negative percentage.

The total of all sales taxes for an area, including state, county and local taxes.

A city or town's public schools are rated on a scale of 1-10 (best) based on individual school performance measures, and state and national achievement tests, and the percentage of students continuing to college. The index attempts to predict the educational achievement of the students.

The dollar amount that the local school district spends on each of its students.

The number of students for each guidance counselor. For example, 415 means guidance counselors in the school district serve an average of 415 students.

The number of students for each librarian. For example, 227 means librarians in the school district serve an average of 227 students.

The number of students for each teacher. For example, 19.1 means teachers in the school have an average of 19.1 students.

Indicates the presence and seriousness of toxic discharges and spills. A score of 100 is best, indicating a lack of discharges. The score is calculated from the number and the expenditures on Superfund cleanups in the county.

The most recent unemployment data for an area. The unemployment rate is expressed as a percentage of the available work force that is not employed. For example, 3.2% means that among every 100 workers, 3.2 are unemployed.

A measure of an area's exposure to the sun's ultraviolet rays. Ten is the highest score, indicating the greatest intensity of sun exposure. The UV index is based on an area's sunny climate, altitude and latitude.

The percentage of the residences which are not currently occupied. A high vacancy rate may indicate problems in the neighborhood, whereas a low vacancy rate indicates a high demand for the area's housing.

Measures the likelihood of violent crime in an area, based on the city and county crime rate, and social and demographic measures for the area. Violent crime is a compilation of four crime categories: murder, rape, assault and robbery.

A measure of the quality of an area's water supply as rated by the Environmental Protection Agency. Higher values are more favorable.

The percentage of the population that works out of a home office, and does not commute to work.