I don't want to pursue this too far, but the figures for the US are not that different. US statistics are a little difficult to compare, because of the way the Census Bureau classifies Hispanics, and so the only reliable figure is "foreign born".

In 2006, the foreign born were 12.5% of the population, much the largest group being from Mexico (3.8%). Historically, this is not a record high, although it is a big increase from 1970. From 1860 - 1920 the figure was around 14%, dropping to 5% in 1970 and rising to 12.5% in 2006.

Probably the biggest difference is that the peak 100 years ago was made up of mainly white Europeans, and today's lower peak is largely Hispanic.

Phil