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BLS Warned About Census Adjustment in December 2011
Posted By Invictus On February 7, 2012 @ 10:40 am In Data Analysis,Mathematics,Really, really bad calls | Comments Disabled
Resistance, however, is futile. Try as I might not to opine on the 1.2-million-one-month-drop-in-the-labor-force, I cannot help but spill a few pixels of my own. So here goes.
Let’s start with last month’s BLS Employment Situation release. It contained a box, on Page 4 (of the PDF), that included the following heading and text (emphasis mine):
Upcoming Changes to the Household Survey
Effective with the release of The Employment Situation for January 2012 scheduled for February 3, 2012, population controls that reflect the results of Census 2010 will be used in the monthly household survey estimation process. Historical data will not be revised to incorporate the new controls; consequently, household survey data for January 2012 will not be directly comparable with that for December 2011 or earlier periods. A table showing the effects of the new controls on the major labor force series will be included in the January 2012 release.
So right there, in black and white, BLS explicitly told its users that January 2012 and December 2011 (and earlier) simply would not be comparable — and that would obviously be the case notwithstanding how the various numbers broke.
Overlooking that caveat is one thing, I guess. Being corrected all over the web and then not correcting and/or retracting is something else altogether.
ADDING: For what little I’m sure it’s worth, whenever I have had a question about an economic release — and that’s dozens (hundreds?) of times — I have picked up the phone and inquired directly of the issuing agency. Guess what? They’ve always been happy to help. Point being, there’s no need to go out with bad information or run your mouth when you have doubts. Of course, this will be of no comfort to the tin-hatters who claim the agencies are in the bag.
December 2011 Employment Situation 
BLS Employment Situation News Release, Friday, January 6, 2012
Article printed from The Big Picture: http://www.ritholtz.com/blog
URL to article: http://www.ritholtz.com/blog/2012/02/bls-warned-about-census-adjustment-in-december-2011/
URLs in this post:
 crushing: http://www.ritholtz.com/blog/2012/02/last-word-bls-decennial-census-adjustment/
 flat-earthers: http://www.ritholtz.com/blog/2012/02/a-few-thoughts-on-the-employment-situation/
 few days: http://www.ritholtz.com/blog/2012/02/taking-apart-the-january-2012-nfp-data/
 December 2011 Employment Situation: http://www.bls.gov/news.release/archives/empsit_01062012.htm
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