TRANSFORMATION AND CONVERSION
For several of the generally applicable indicators there are internationally recognized methods for the transformation of data into common units (e.g. the calculation of greenhouse gas equivalents). However,
for many other parameters, such as hazardous waste, there are no commonly agreed methods for this type of conversion. In these cases car e needs to be taken when data ar e transformed, and the method of transformation should be clearly described.
Eco-efficiency information will generally be aggregated and reported for an enterprise as a whole, rather than for individual products and facilities. This is especially so when reporting to outside stakeholders (e.g. in a corporate sustainability report), and for large
companies with tens or hundreds of facilities and products, distributed worldwide. Some businesses may choose to report enterprise, segment
and/or product level eco-efficiency performance. But most are likely to limit it to the enterprise level to pr otect confidential business information, or to keep volume limited.
While aggregation will often be necessary, it is likely to obscur e
potentially important information about an enterprise’s eco-efficiency performance. For example, different
types of unrelated emissions, or emissions across different geographic locations, may be added together,
preventing a valid assessment of potential influences on the local environment. Eco-efficiency estimates
from different products, processes, or geographic areas may be combined and averaged, obscuring details about the
performance of individual units. As a result, aggregation of data should be done carefully, and with transparency to
the end-user, so that the limitations of the information can be well understood. This is especially the case when data ar e reported publicly, where comparisons
between different companies, processes, or products could be made.
INTERPRETATION AND BENCHMARKING
Eco-efficiency reporting serves to track performance, identify potential
improvement opportunities and document progress. Within a company
benchmarking could be made to track year-to-year performance and to compare against targets.
For comparisons between companies it is important to recognize the inherent diversity of business. Comparisons should be made only when the companies being compared provide the same product/service (e.g. electricity). It is also important to recognize that the product portfolios of different businesses often change, and that this may affect eco-efficiency performance, independent of a firm’s
environmental activities. The impact of such changes should be discussed in reporting eco-efficiency data, to
allow users to interpret year-to-year trends accurately.
measurement and reporting in practice
“Interpretation of the data is the central issue of performance evaluation and reporting. Decision makers want to know what their own figures mean for the various businesses in relation to peers and targets. It is important to have trends over several years for good interpretation.”
EXPERIENCE SHARING MEETING IN LONDON, JULY 6/7, 1999