The author does a nice job reconciling seemingly diverse findings about happiness trends and identifying the underlying reasons for differing conclusions.

Over the past decade or so there have been many Positive Psychology articles exploring the relationship between money and happiness. Myers (2000), Diener and Oishi (2000), Blanchflower and Oswald (2004), and Layard (2005) amongst others have presented research which suggests that increasing wealth does not buy happiness (this graph illustrates this point for the USA).Happiness is on the up… The good news is that according to a new study by Inglehart, Foa, Peterson and Welzel (2008), happiness is actually increasing: in this longitudinal study between 1981 and 2007, happiness levels went up in 45 out of 52 countries. And contrary to what you might conclude from Myers’ graph (mentioned above) the US is one of those countries which shows an upward trend in happiness (p276). So how do we explain the apparent inconsistency between Myers and Inglehart et al?