Hurricane Irma caused severe damage in St. Thomas and St. John in the U.S. Virgin Islands. Puerto Rico also suffered damage from Irma. Irma was a Category 5 hurricane when near the U.S. Virgin Islands and Puerto Rico.
Hurricane Maria made landfall in St. Croix in the U.S. Virgin Islands and in Puerto Rico on Wednesday, September 20, causing catastrophic damage. These areas already had suffered damage from Hurricane Irma earlier in the month.
What was the impact of the storm on establishment survey response rates for Puerto Rico?
The CES program reviewed, and continues to review, all aspects of its estimation procedures to determine if any changes are necessary. For the release of September 2017 Puerto Rico estimates, the collection rates in the affected areas were within normal ranges, and the CES program determined that no modifications to the current methodology would be made. Survey response rates were lower than average for the October reference month but continued to improve to near average levels by December. A summary of the survey response rates by reference month for Puerto Rico is included below.
Did CES estimation procedures change for the September through December 2017 data for Puerto Rico?
Research indicates that while both the business birth and death portions of total employment are generally significant, the net contribution is relatively small and stable. To account for this net birth/death portion of total employment, BLS uses an estimation procedure with two components: the first component excludes employment losses due to business deaths from sample-based estimation in order to offset the missing employment gains from business births. This is incorporated into the sample-based estimate procedure by simply not reflecting sample units going out of business, but imputing to them the same trend as the other firms in the sample. This step accounts for most of the birth employment. Given the impact of hurricanes Irma and Maria, reported zeroes were used to calculate the final October and preliminary and final November estimates for Puerto Rico to reflect likely changes in business birth/death patterns in Puerto Rico. The second component is an auto-regressive integrated moving average (ARIMA) time series model designed to estimate the residual birth/death employment not accounted for by the imputation. This second component was not modified for final October or preliminary November estimates for Puerto Rico. See https://www.bls.gov/web/empsit/cesbd.htm for more information on the CES net birth/death model.
|Reference Month||Survey Response Rates||Birth/Death Component|
|September final (September preliminary estimates were not published)||Normal range||No changes to methodology|
|October final (October preliminary estimates were not published)||Below normal range||Reported zeroes were used in estimation|
|November preliminary estimates||Low end of normal range||Reported zeroes were used in estimation|
|November final estimates||Low end of normal range||Reported zeroes were used in estimation|
|December preliminary estimates||Low end of normal range||No changes to methodology|
How were establishment estimates for the U.S. Virgin Islands affected by the recent hurricanes?
Because of the devastation caused by Hurricanes Irma and Maria, the U.S. Virgin Islands was not able to conduct normal data collection activities for its establishment survey for several months. In turn, given the lack of adequate sample data, preliminary September, October and November estimates for the U.S. Virgin Islands were not published. The latest estimates for the U.S. Virgin Islands were revised August 2017 estimates published on October 20, 2017. As of mid-December, the U.S. Virgin Islands was able to resume data collection and produce revised estimates for September, October, and November 2017 and preliminary estimates for December 2017. Survey response rates were below average but were adequate to produce reliable estimates. No modifications were made to the estimation methods for the U.S. Virgin Islands. These data were published on January 23, 2018.
Last Modified Date: January 24, 2018