I know the political views of around 50 people. I don't talk about politics all the time though, so I don't know how their views change and develop in any great detail. Also these people are ones I just happen to know and they aren't a representative sample. But nonetheless as a rough estimate I could make a guess that if 1 person I know changes their mind that is equivalent to 2% of the population. Not very scientific, but better than reading the newspapers.
