The media has been mis-reporting the pace of illegal entry when it gives the impression that the arrival of the Trump administration led to a drastic reduction in illegal crossings, based on apprehension volume. Media reports tend to cite a 40% or greater reduction. A more accurate decline is 25%, and the monthly trend through August shows shrinking of the amount of decline.
Apprehensions rose strongly during May – October 2016, before the election, to a peak of 68,000, well above the monthly average in the past five years of about 45,000. Apprehensions Nov 2015 through August 2016 were a 462,000 vs 320,000 the Nov. 2016 – August 2017. That is a 27% reduction.
From November 2016 through April, 2017, the monthly rate did drop precipitously to about 15,000. Since then it has risen every month to 31,000 in August. After one excludes the very high August of 2016, the August average of the prior four years is 39,000. This indicates a 25% reduction. Trend lines suggest that the reduction since the election will decline. The next 12 months may be about 350,000 vs an average of about 400,000 if one leaves out the particularly high year of 2016.
Source is here.