Not according to the author of this piece, Jonathan V. Last, which is linkrd below. Last also said on C-Span's BookTV last week that the fertility of Latinas in the USA is also dropping fast.
The result is that from 2005 to 2010, the U.S. received a net of zero immigrants from Mexico...
Michael Barone also wrote within the last year that net migration from Mexico was zero. It's our booming economy, not. The number coming is the same as the number going home. IIRC, Mexico's annual GDP is about 5 %.
I’ve seen those stats also. Not sure of the validity, but certainly possible.
One example here in the midwest was that many non-union construction jobs (largely single family home construction and repair) were held by Mexicans, and most of that work is gone.
I agree the economy has had a big affect on in-migration, but that is temporary (I hope).