That's the net balance, the net gains. The net gains are linguistic transfers. For example, in Quebec, according to the 2001 census, 591,000 citizens reported that their mother tongue was English, whereas 746,892 citizens declared that English was the language they used in the home, which shows what, in demographics, are called language transfers. There are people who have abandoned their mother tongue in order to speak mainly other languages in the home.
On February 1st, 2007. See this statement in context.