THE SUSTAINABILITY INDICATOR CONCEPT

Daphne Greenwood and Michael Mueller
February 2000

What is sustainability?

The classic definition of sustainable development is "development that meets the needs of the present without compromising the ability of future generations to  meet their own needs" (Brundtland Commission, 1987). In economic terms this is development that preserves or enhances present day capital endowments used to produce income and other quality of life measures.  Capital endowments include not only physical capital owned by private businesses but public infrastructure, natural capital (resources), and human capital (the stock of skills and knowledge)
(For more on sustainability issues and the use of indicators, see the reading list on this web site).

Why do we need sustainability indicators?

Increasing concern for the quality of life, in Colorado and around the country, has accompanied the rapid economic growth seen here and in many other areas. Conventional economic indicators (employment, prices, personal income) are based on the production of goods and services and fail to measure "bads", such as decreases in air quality and increase in commuting time or crime rates.

To remedy this gap, a nationwide movement to develop sustainability indicators has grown in recent years. Sustainability indicators encompass a wide variety of measures (public health, crime rates, education and child welfare data) and are distinguished primarily by two characteristics. First, they have generally been a compendium of measures developed in community meetings through a consensus process. Whether many of the indicators are statistically correlated with each other (and therefore, redundant) has not been adequately explored. Second, they are dependent in great measure on what data is easily available and what groups participate in their process. For this reason, there is little comparability among measures between communities. Often, the measures are limited to a subset of interest, such as public health measures or child-sensitive measures.

We believe a more comprehensive set of indicators is needed. We also believe that the rigorous approach to analytic and measurement issues practiced by economists can contribute greatly to improved measures of sustainability. The classic definition of sustainability is "development that meets the needs of the present without compromising the ability of future generations to meet their own needs" (Brundtland). In conventional economic terms this might be translated as development that preserves or enhances initial capital endowments – human capital and natural resources as well as physical capital. Social capital, or infrastructure is also an important part of the full endowment of capital (Tietenberg and Ekins)

The connection between sustainability and capital provides a framework for determining a coherent set of sustainability indicators. The best sustainability indicators show changes in one of the capital stocks -- physical, human, natural, or social.  Clean air and open space are parts of our natural capital stock. Highways and school buildings are part of our physical stock of infrastructure.  High school and college graduates are part of the human capital stock.  All of these stocks can produce consumable goods  or directly  provide consumption services (as in the case of clean air and open space). They can also be used in ways that replenish, enhance, and preserve themselves or that deplete themselves. 

The uses of various capital stocks are often linked, an example being the stock of clean air and of uncongested highways. Sustainability indicators need to show the connection between these stocks. The number of good quality air days is an indicator of clean air, but asthma-related admissions shows the link between natural capital - clean air, and human capital - good health. Changes in the stock of the full endowment of capital and the inherent linkages between them in use provide a rigorous framework for development of a set of meaningful, coherent, and analytical sustainability indicators.

How do sustainability indicators differ from quality of life indicators?

Typically, community indicators include a range of measures of things people care about that are not measured in conventional economic indicators. These might include park acreage per citizen, access to cultural events, or the percentage of children who have been immunized. Most of these could be termed "quality of life" indicators. They help measure whether the values of the community are being realized. It is important to add quality of life indicators to the set of conventional economic indicators in order to be able to assess whether increased income or a low unemployment rate is resulting in a higher standard of living for residents. Also, some elements of a higher quality of life (more parental time with children) might come at the expense of rising incomes or job growth.

However, most quality of life indicators are not sustainability indicators. They are measures of current well-being rather than indicators of the capital stock. This is not always the case. Some measures of health (infant mortality) or educational achievement (high school graduation rates or achievement test scores) may serve both as indicators of the quality of life and of the quality of the stock of human capital. But we believe it is important to keep in mind which function, or functions, each measure is serving.

Sustainability indicators in the U. S.:

The concept of the Genuine Progress Index (vs. the Gross Domestic Product) has been developed by a group called Redefining Progress. They "seek to shift the prevailing definition of progress from one based exclusively on a growing economy to one that resonates with people’s sense of the quality of their lives." Many local groups have drawn on their work, and their site is also a source for finding out what groups around the country are doing. 

Another national group often referenced in the sustainability discussion is Hart Indicators. Their founder, Maureen Hart, has developed a rating system for community indicators which scores them high if they are directly related to the capital stock concepts mentioned in our discussion above, and lower if they relate to current outcomes. 

An example of a statewide indicators report is provided by the Maine Economic Growth Council, Measures of Growth 1999. The Maine indicators are slanted more toward economic growth than quality of life indicators. However, the report is an excellent example of how each indicator can be presented using text and graphics. 

Other examples of community indicators can be found at

Sustainable Seattle 

Jacksonville, Florida: 

City of Austin: Sustainable Communities Initiative

Sustainability indicators in Colorado

Many of the efforts in Colorado appear targeted to information on children or juveniles, or on public health. The Colorado Trust’s Healthy Community Initiative has encouraged efforts in Roaring Fork/Grand Valley, Boulder County, Archuleta/LaPlata/San Juan counties (through Operation Healthy Communities), Montezuma County, San Luis County, and Mesa County. However, many of the associated web sites appear out of date or even inaccessible at present.

Denver, Piton Foundation:

La Plata County: 

Mesa County: 

San Luis Valley

 The Colorado Department of Public Health and the Environment is also collecting a limited set of measures, etc. for front range communities.

In Colorado Springs, a "State of the Environment report" was prepared in 1999 by the Environmental Alliance of the Pikes Peak region (tops@usa.net) using information currently available. A Community Health Indicators report produced by the El Paso County Department of Health (February 1999) also gives some valuable information for building a set of local indicators. A recent report from the Southern Colorado Economic Forum included some quality of life measures such as performance on high school assessment exams.

Developing usable sustainability indicators

A more rigorous and scientific approach to what to measure and how to measure it could contribute to the success and use of sustainability indicators to supplement conventional economic measures. This would enable policymakers to make decisions which are better informed as to their impact on the stocks of physical, natural, and human capital and therefore on the future standard of living.

Some new information must be collected, but often what is needed is to

  • aggregate, preserve and make readily available information already collected by city or county governments
  • improve the quality of measurement to increase reliability
  • recognize linkages between the various measures.