GDP vs Happiness

While taking a class on Macroeconomics, I was intrigued by two examples cited, where economists tried to evaluate if the GDP has a bearing on people's extent of being happy. The evaluation question in itself is a natural consequence of self-introspection on the behalf of the macro-economists, because they are trying to find out if all the effort and focus bestowed on GDP is really worth something else than the sum of the produce. The first example was for US - and this is the graph which was referred to:

The researchers observed that the increase in GDP did not have any effect on the general level of happiness in the US. At the same time, another example - East Germany - was cited to also show that the US trend does not hold good for all counties.

East Germany's example was cited more importantly to analyse what happened when the circumstances of the people was changed drastically. The observations are very different from the observations in the US, and the survey showed that the level of happiness did increase with the increase in GDP.
Somewhere, the conclusion seems to be that there is a certain threshold of income up to which the GDP/happiness co-relation holds well.
No doubt this endeavor is a noble one, since GDP is the measure of how modern economies hold up. Correspondingly, there are ways which psychologists have been trying to measure human satisfaction levels. Maslow's hierarchy of needs is one such way.
GDP, by virtue of what is stands for, does seem to correspond to the second level in the hierarchy - safety needs. But then that might not be enough. From here on, the discussion becomes very subjective - that of respect, and love, and self actualization, which pertains to feelings of the individuals who are part of the system and the economy.
It seems GDP became a little over ambitious thinking it could influence an ever elusive emotion of happiness. It contributes surely and the examples cited are perfect to show how much.