I heard last night that MI estimates we only apprehend 5% - 10% of the border crossers. Using the 1,000,000 number of apprehensions you mention, that would mean, according to MI's apprehension rates, somewhere between 5,000,000 to 10,000,000 come across every year. At this rate there will be no able bodied working class people left in Mexico within a couple more years. I think something is drastically wrong with the numbers and rates. Would like to see some actual stats and or reliable numbers.
The problem with the way they estimate border crossers is that they have a doctrinal assumption that they only catch 10% of the crossers. So if something happens that causes them to catch twice as many they assume that means twice as many people tried to cross. The entire illegal alien guesstimation system is built around this presumption that the effectiveness of the border never changes. There's a similar built in assumption when they start talking about the amount of drugs that come over the border. It's a great way to get increased federal funds because no matter how well they do their stats will always say they're no where near controlling the problem.
I believe that's Mexico's goal. They don't have to subsidize infrastructure to provide jobs, yet they reap the benefits because "dual citizens" are still taxed at the same rates - Mexican governments are in a win-win position.
As long as illegals send dollars "home", unscathed by reimbursements for their use of US services, there never will be any incentive for local Mexican governments to seek better for their citizens.