But do you think you are the exception or the norm? I've looked into Zurich real-estate last year and 1000CHF wouldn't even come close to the prices I saw for a small 2br.
The idea of the average adjustments is to get a general idea of the cost of living.
I am an exception as I rent a room for 500 CHF (the norm is 750-1000 CHF). Also, I pay 200 CHF for the cheapest insurance. Then, I budget about 300 CHF to buy food.
If you insist on renting a nice 2bd aparment, you can do so for 2500 CHF in Zurich-city. If you move just slightly out of town, prices drop. I live on the southern end of town and my company is in the north. It takes me only 35 min to go through the whole city (Zurich is rather small).
In my opinion, cost-of-living averages give a misleading idea because people mentally give "cost of living" equal weight as to net-salary.
Although my life in Zurich costs more than my life in Munich, the ridiculous-high salaries and excellent working-conditions (I pay only 16% as taxes) make me feel that I win the lottery each and every month on pay-day. However, in case of sickness I would probably take a day off work and go to Germany (45 min trip) to go to the doctor there as doctors in Zurich also earn double as much.
It's easy to say COL is innacurate if you're a single person willing to live a frugal lifestyle. These are typically based on average family size, so in the US, that's a family with 2.3 children. I'm not sure what the average family size is in Switzerland.
My point being- I used to be able to save a tremendous amount of money; something like 65% of my after tax income, when I was single. Now that I'm married with two kids, I'm only able to save a much smaller 35%. I still live frugally, however, when you have young kids going to school, it's no longer possible to live like a monk. School is expensive, and kids are expensive to raise.
Cost of living is a very valid metric. At a minimum, it reflects the local property tax rates, which are basically the cost of schools and other government services.
Even so, the way a family with 2.3 children lives can differ significantly between cities. A successful middle-class family with 2 children isn't abnormal if they live in a 2-bedroom apartment in NYC, but they are well outside the norm in most other cities.
The idea of the average adjustments is to get a general idea of the cost of living.