It's been record levels since the beginning of Obama's term in 2008 and climbing every year. Reason is immigration laws since then are incredibly lax for foreign students. If you want Canadian citizenship show up here for ESL private school, a hair academy, a university, any accredited course and you can obtain a temporary work permit while attending classes (and for a period afterwards). This allows a local company to offer to sponsor you for full time employment, which eventually leads to citizenship. Vancouver is filled with Brazilian accountants who got in this way, they came here to take ESL, and went to go work for some accounting firm like KPMG with their degrees they have from Brazil.
Edit: they changed the laws in 2014 to make this a little more difficult, but temporary work permits are still available for any student esp somebody going to university/college. These always lead to full-time offer and citizenship.