Unlike other states, New York continues to have a growing undocumented population, according to the latest estimates from the Pew Hispanic Center. (I wrote about the center’s new study in today’s Journal News and in this blog.)

Researcher Jeffrey Passel puts the statewide figure at about 800,000 to 1 million, up from 350,000 in 1990 and 725,000 in 2000. There was a dip in the number in 2005, to 625,000.

Passel cautioned against focusing on any year-to-year changes, but noted that New York’s increase is substantial:

It’s very clear from the data we have that the immigrant population overall is up in New York over the last three years. And based on this analysis, it appears that it’s up in part because of undocumented immigration.

In a conference call yesterday, Passel was asked repeatedly whether there was any evidence that immigrants were returning home in greater numbers. Anecdotes abound, given the job shortages and increased enforcement, but there is no data showing a change, he said. A lot of people leave every year, but that’s always been the case; it’s just that fewer are arriving. So the overall estimate on illegal immigrants is still about 12 million.

Mexican studies have found no change in the numbers of people returning from the United States. Passel cited Mexico’s quarterly employment surveys, which found large numbers of people returning, but not a change from previous years.