The border fence is 700 miles long—and counting. Border Patrol apprehensions have been dropping for three years. Remittance outflows to Mexico were down nearly 3% in the first three months of this year from the same period last year. A poll of migrants by the Inter American Development Bank in April confirms that fewer are sending money back regularly.

”Evidence” for a decline in the illegal immigrant population has been limited to these anecdotal items—until now. A new report by Steve Camarota finds that the illegal population fell by some 1.3 million, or 11%, through May 2008 after peaking in August 2007 The study is based on the Current Population Survey, widely regarded as the most accurate gauge of U.S. population available between Census years.

We feel justified in crying out ”We told you so!” For years we have tracked monthly trends in Hispanic and non-Hispanic employment, highlighting the disproportionately large advance in Hispanic labor since the start of the Bush Administration.

Since last summer, however, we’ve noted what can be reasonable called a sea change: Hispanic employment growth rates started lagging non-Hispanic employment growth rates.

Our last employment update, published in early July, contained the following prescient observation:

”VDARE.com’s American Worker Displacement Index (VDAWDI), calculated as the ratio of Hispanic to non-Hispanic job growth indexes during the Bush years, fell to 122.8 in June— its the largest decline since January. Since peaking in August, VDAWDI has encountered upside resistance:”

”Our general economic funk undoubtedly plays a role, dissuading legals as well as illegals from coming to these parts. But there are plenty of reasons to suspect that a diminished influx of illegal workers is playing the larger role.”

The post-August 2007 reversal, now confirmed by Camarota, was quite evident in our last VDAWDI graphic:

Is it just the economy? No, stupid. Camarota finds that employment of less-educated Hispanic immigrants began to fall well before their unemployment rate started to rise, noting:

”This suggests that the fall in the size of the likely illegal population was caused by enforcement rather than deterioration in the economy. However, the rise in unemployment now may be acting in concert with increased enforcement efforts, making it increasingly difficult to determine the relative importance of the economy or enforcement if the current decline continues.”

To be sure, Camarota’s illegal alien population figures are estimates. His data source—the Current Population Survey - does not ask immigrants their legal status. This egregious flaw forces researchers to estimate the illegal alien population using various markers—citizenship status, age, country of birth, level of education, household size, etc.

Some have abandoned CPS for other data sources. They report the illegal alien population may be as high as 30 million.