collected years before publication. In addition, data users argue that some characteristics of building energy consumption change relatively frequently and therefore that energy consumption data would be more useful if they were captured on a more frequent basis.
Just before this report went to print, the data that had been collected for the most recent CBECS were deemed unusable four years after the reference period (2007). Even in the best case, the result would have been an eight-year time lag between one round of the survey and the next round that was usable. However, a decision to suspend the 2011 data collection because of insufficient funding will make the lag even greater. These are unusual circumstances, and they have put stakeholders who rely on the CBECS data for research and decision making in a very difficult situation.
For the purpose of discussion in the sections that follow, the panel assumes that the CBECS data collection will resume on at least a quadrennial schedule in fiscal year 2012.
Rotating Panel Design for the CBECS
One option for addressing data users’ need to have quicker access to the data is to implement a rotating sample design, which would make more frequent data releases possible. This could be done by dividing the sample into four subsamples and collecting the data over a four-year period, instead of once every four years. Data could then be released annually, with each release containing one year’s worth of new data combined with data from the previous three years in order to achieve a sufficiently large sample size that will enable EIA to release an amount of data that is comparable to what is released under the current design.
This design would have several advantages, besides offering faster access to the data. For example, while the goal would be to have roughly the same number of completed interviews at the end of the four-year cycle as would have been collected with the standard pattern of collecting data once every four years, with self-contained annual samples, the rotating design would not require a commitment to four full years’ worth of interviews upfront, which could be an advantage if fluctuations in CBECS funding persist. The continuous sample design would give EIA more options when faced with a substantial budget cut, for example, by making it easier to reduce the sample size without having to sacrifice the entire survey. Furthermore, the new design would also increase EIA’s ability to be flexible in terms of testing new data collection approaches because testing could be performed on one year’s