I have seen lots of graphs showing rates of immigration to the U.S. over time, but I just found this graph showing the rates of emigration from Mexico from 2006 to early summer of 2008 (from the Migration Information Source website; this is all emigrants, regardless of destination, though of course the vast majority will be to the U.S.):

A quick note on the data: Since it required someone from a family to be left in Mexico to be asked about family emigration patters, it doesn’t include those situations where an entire family left all at once; however, my understanding of immigration patterns is that this type of immigration is a minority of all movements, since most families prefer to send one or two family members to get a foothold in the host country.

As we see, there’s a general overall downward trend during that time period, which isn’t surprising given the downturn in the U.S. economy, especially the construction industry. The Mexican government reports that remittances sent back to Mexico are down this year as well.

 There is also a seasonal pattern, with the period from August to February of each year being the lowpoint and then picking up again in the spring. My first thought, since I study agriculture, was that this might have something to do with the growing season and when agricultural workers are needed in the U.S., but of course it’s a stereotype that most Mexican immigrants are field workers, so that’s probably not it.

Any thoughts on what might explain that pattern?