Don't the time frame of the truce between the Cullens and the werewolves don't fit in Twilight?

What I mean is, in the book, the Cullens and the werewolves made a truce about 70 years ago, and I remember somewhere in the first novel being mentioned that the Cullens only moved in here 2 years ago to Forks. How could they have moved into Forks two years ago and they made a pact 70 years ago, allowing them to stay in Forks? And if they were in Forks 70 years ago, wouldn't anyone notice their unaging family?