|Original graph: C&EN, 11/1/10, 88 (44), pp 38.|
Modified by Chemjobber
My take home from the graph is this: you can see the last three recessions (90-91, 2001, and 12/2007-) represented in red in the modified graph.* In my experience, this is evidence that modern unemployment in chemistry is at least somewhat correlated with the overall unemployment picture.
Anon's real question is "what does the gap mean?", i.e. "Why isn't the ACS unemployment rate also 10% right now?" My answer: honestly, I don't know. It's certainly not the "sheltering" hypothesis in my opinion. Whether the ACS salary survey undermeasures unemployment is, of course, a different question.
*Important to remember: unemployment is a lagging indicator of the economy.