Why you starting only at 2013 with your historical rendition and thereby prediction?
The further we look in the past - the less relevant it is. What happened too long ago doesn't matter. I had to cut-off at some point.
And you really have any kind of reasonable belief that 2x per year would be a sustainable model in any kind of long term projection?
Yes, not not too much long-term. Maybe just 2020-2022.
I think 2x per year is conservative enough estimate to last that long.