Norway's 1500m success in the history of the country pretty much starts and stops with the Ingebrigtsens. They are 1st, 3rd, and 4th on the all-time list. Remove one family, you've got 2 guys ever to run sub 3:36. Accounting for population, 5.5 million vs 340 million, the two countries are pretty much the same. You've got 5 guys ever sub 3:36 (3 from one family) The US has 120. That's a ratio of 61 to 1, which happens to be the population. But actually the ratio of population was lower as you go back in time because the US population is consistently growing at a faster rate than Norway in the past 70 years. If you remove the best family of each country from the results, then the US has a way better ratio of fast 1500m runners per population, since Norway would then only have 2 sub 3:36 guys and the US would have 118 (most from one family is 2).