Which nationalities are trusting

Reading Dan Ariely’s Predictably Irrational I was struck and concerned by his data which suggested that once social norms of reciprocity break down it is difficult to regenerate them. In other words, social capital can be thought of as a limited nonrenewable resource, at least proximately. On the macroscale Peter Turchin offers up a historical theory where social capital translated into group cohesion serves as the motor behind the rise & fall of states. And over 10 years ago Francis Fukuyama wrote Trust: The Social Virtues and The Creation of Prosperity, which surveyed differences across nations in terms of how economic and social variation hinged on the trust, or lack of, across non-kin within a culture.
As it happens, both data sets in the World Values Survey has a binary question on trust:

Generally speaking, would you say that most people can be trusted or that you need to be very careful in dealing with people?
1 – Most people can be trusted
2 – Can´t be too careful

Below I report the % who answered #1 for all the nations in the two data sets. Some nations are therefore duplicated.

There are major discrepancies between the two separate data sets for some nations (e.g., Iran). It could be that the samples, all in the range of 1-2 thousand individuals, are not representative. Or, it could be that the wording of the two questions was slightly different in style, and that difference resulted in very different responses. Finally, there could simply be an error in the reporting of the results (I’ve actually seen this in a few of the results, since it is obvious that they flipped the proportion who do, or don’t, believe in god in same cases).
But there are some general trends which seem likely to be robust. Scandinavians are trusting. Latin Americans are not. For the ex-Communist nations, and a few specific cases such as Rwanda, the lack of trust can probably be attributed to relatively recent historical events. Oh, and all I have to say: go long on Vietnam!