The migration numbers prove...nothing

The U.S. Coast Guard intercepted 2,134 Cubans trying to reach the United States without a visa last year – that’s 25 percent fewer than the year before, according to figures from the just-concluded 2008 fiscal year reported in the Herald.

Actually, the Coast Guard’s data tables show that 2008 interdictions were more than 25 percent lower than in any of the three previous fiscal years.

What conclusions can we draw?

None at all, in my opinion.

Everyone knows that huge numbers of Cubans would like to emigrate to the United States. After all, half a million applications came into the U.S. consulate when the visa lottery program was instituted during the Clinton Administration, with many applications on behalf of entire families.

But there’s a temptation to discern big political trends in the ups and downs of migration statistics – a feat that the actual statistics don’t allow us to perform. (If you don’t agree, maybe you would want to argue that the 25 percent drop in interdictions tells us that more Cubans are staying put because they are increasingly hopeful and confident under the Raul Castro government.)

Kidding aside, here’s the problem.

Relative to the Cuban population, the numbers of interdictions and Cubans who arrive without visas are very small. What’s more, there are so many factors in play that it’s impossible to prove a cause when the numbers tick up or down.

2,134 is the number of those caught at sea during fiscal 2008, compared to 2,868 in 2007. That decrease is worth examining if we know that it correlates with a decrease in attempted departures, but we don’t know that that is the case.

Regardless, let’s set that aside and ask anyway: Why did the number go down?

It could have something to do with changes in the Coast Guard’s skill or luck or deployment patterns. Or, it could be caused by changes in the skill or luck of migrants or those who smuggle them.

Or, if you consider the fact that alien smuggling is an established business, it could be caused by rational market behavior: It may just be that people in Miami who want to get their relatives out of Cuba have learned that the lowest-risk option is to pay smugglers who operate on the Mexico route, bringing Cubans to the Yucatan then arranging their trip north to cross the Texas border. That would certainly explain less traffic encountered by the U.S. Coast Guard.

On top of that, there’s no way to take statistics about smuggling – or statistics that combine departures by smuggling and departures by rafts or other vessels – and draw conclusions about changes in conditions in Cuba. The incidence of smuggling, at least in part, is tied to factors that have nothing to do with Cuba, such as Miami families’ confidence in the smugglers’ ability to defeat law enforcement, or the families’ ability to afford smugglers’ fees.

We might know something about the connection between illegal departures and the public mood in Cuba – if we knew that Cubans’ perceptions of the effectiveness of U.S. enforcement were constant, and if we had actual data on the number of Cubans who attempt to leave by means other than smuggling.

But we don’t have that statistic, and we never will.