In the weeks following the terrorist attacks of September 11, disruptions of postal service made necessary by the detection of contaminants in the mails have had some limited impacts on Bureau of Labor Statistics data collection operations.
The response rate for the October Producer Price Index was reduced to approximately 80 percent of its normal level. A review was undertaken to evaluate the impact of lower response rates on survey estimates. No unusual effects were found.
Postal service disruptions did not affect the overall level of Current Employment Statistics (CES) sample receipts for October. Approximately 80 percent of the CES sample data are collected through automated methods and about 20 percent of the sample respondents report by mail. For the mail-collected units, October receipts were at a normal level.
Similarly, despite the disruption in postal service, response rates for the Import and Export Price Index surveys for October were not appreciably different from normal levels.
The September 11 attacks themselves occurred during the reference week (September 9-15) for the Current Population Survey (CPS) of households. Data collection began as regularly scheduled on Sunday, September 16, and continued into the week of September 23. Octobers data collection efforts also were conducted on their regular schedules. The September and October survey response rates, both nationwide and in the New York City area, were normal. The Current Population Survey is based entirely on telephone contacts and personal visits; it was not affected by special mail handling and delays.
The events of September 11 also occurred during the reference period for the Employment Cost Index (ECI). A review of ECI survey responses undertaken to evaluate the impact of the situation on the surveys cooperation rates by industry and any impact of nonresponse on survey estimates found no unusual effects.
Last Modified Date: November 9, 2001