This weeks blog post on my site is about who passes and who doesn't pass Norskprøve 2 and 3.
In short, those who passes are people from English speaking countries and whos stay in Norway has been shorter than 1 year. Particularly for the group who are from English speaking countries, there is a almost the same pass rate for both Norskprøve 2 (A2 level) and Norskprøve 3 (B1 level). For other groups there is usually a significant lower pass rate for Norskprøve 3.
The main reason for significant better performance among people speaking English is naturally the similarities between the languages. This is particularly relevant for the B1 test, where grammar requirements are more strict.
More interesting is the fact that the group of people who have been 1 year or less in Norwegian perform significatly better than all other groups. Those who have been in Norway for more than 5 years tend to do very poorly on the tests, particularly Norskprøve 3.
Of course, the measurement is only on length of time in Norway and not on length of time you have been studying Norwegian. So only thing we can say with certainty is that staying for more than 5 years doesn't guarantee that you will be able to perform on a Norwegian test.
On the other hand, intensive study for a shorter period of time will give you a huge legs up when learning a new language.
Considering that in the group "less than one year in Norway" we don't have only people who have been there for 11 months. We probably have people who have been there for 8 months or even less.
So, not only can you learn Norwegian up to a B1 level in a very short time. This way of studying with intense focus is the best way of studying. Try to avoid the one-two hour a week scheme for years. Instead try to study intensely for a year.