I've seen numbers along the lines you described, and I'm sure we can get them for you. It's true that people's outcomes do improve over time, but they don't look at all as they did for previous generations. The numbers I saw were pretty recent too. We think by getting to people with more funding when they first arrive, especially for language training, people will have better outcomes.
One of the differences between this generation of immigrants and the previous one is the source countries. The source countries in the past tended to be countries with Latin alphabets, where it was typically easier for people to learn language skills. Today we have a lot of people from Asia, who may not have had the benefit of a Latin-based alphabet, so it's more difficult for them to pick up the language skills. We want to put as much funding into that as we possibly can, so people who have great skills and abilities can put them to work right away.