In reply to HakanT:
As far as I know - there's no simple way (or else there would be almost no risk with opening a new business) to calculate whether to build a bouldering wall or not. You naturally have to have some assumptions, because you can't do research on your customers because you have no customers.
Probably some good places to start are to visit a variety of bouldering walls and get some info on busiest times, and how people arrive, and whether they look like they came from home or after work. This you can use to get an estimate of how important 'transport flux' is - i.e. which streams of nearby public transport will contribute to your customer base and by how much, assuming a standard 'how interested people are in bouldering' rate (which you might want to check - e.g. the average income and age will determine how likely people are to boulder).
A second tool which is a rough gauge of popularity is google search trends:
Interestingly the google search trend for bouldering is close to flat:
https://www.google.com/trends/explore?q=bouldering
This shows that bouldering has not really taken off (yet, if it does). So you could be onto a winner by investing early.
Compare that to say the keyword 'vegan', which is exponential over the same time period (which indicates something that has taken off).
https://www.google.com/trends/explore?q=vegan
The Olympic popularity surge has yet to occur, and may take many years to occur (if it even does). Because it has never occurred before for this particular 'sport', you can't quantify the effect accurately. You might want to assume that other new Olympic sports are a good model for this, but ever since seeing this curve - my ideas about what will and won't become popular became changed.
https://www.google.com/trends/explore?date=all&q=vinyl
A bathtub curve in the wild.
(e.g. if you had predicted in 2011 how popular vinyl would be in 2016, you'd have guessed some amount 3x lower than it actually was - which is what actually happened, and that drove the price even more higher because the supply was low due to projected demand being low).
Lastly here's a trend which had some kind of exponential popularity, but has began to decay heavily (hehehe):
https://www.google.com/trends/explore?date=all&q=zumba
Look at those little spikes - those people thinking 'hey I'll get fit in January - no more fat me! I'll be zumba fit'. But the data knows that's a lie.
I would suspect (but have no data to support) that this meant the closure of many zumba gyms and classes.
So with all of this in mind - it's hard to say. For more bouldering gyms to open and to stay open, there will need to be an increase in popularity and sustain it. Personally I think that it will get an increase in popularity within the next 10 years - and that it will be sustained growth.
Post edited at 15:05