On the downgrade in potential and the range for potential, I'd like to emphasize our potential is really reflecting, primarily, the downgrade that we made to business investment, because that business investment that we still have in there represents what we call capital deepening, which means that labour productivity improves.
Now, the downgrade in the investment is primarily in the energy sector, and so it's what I was talking about before, which is we're in this destruction phase, or the phase where the negatives in the energy sector are really outweighing the positives in the other part of the economy. You'll notice that those ranges stay lower for a while but then start to move back up as that transition progresses. You'll see potential output growth, that range, moves up starting in 2018 and going up to 2020, which is the end of our estimate.
I think another factor here is just labour. The more people you have in the labour force, the more you have adding to potential.
What we've seen is a lot of people were discouraged and out of the labour force. Over the last year, we've seen many prime-aged people come back to the labour force. It's possible that even more will come back, particularly younger people who left the labour force after the crisis and over the last couple of years.