That assumes no other teams made improvements.
Here's the thing
If the Nats had simply beaten the teams that were bringing up the bottom of the ranks like, Houston, Marlins, Dodgers, etc., they could have been in the playoffs LAST year.
Continue to do as well as they did last year against teams like the Phillies, Braves, etc., and then WIN the series against the lower tier teams and the Nats could certainly get there this year.