Funnily enough when you look at the countries in the 'happiness index' they all happen to be countries which fundamentally have pretty good underlying economies (and often they tend to be from european countries that have decent social support structure).

Well-being is probably a third-order effect from a strong economy, good healthcare / social care, culture and a variety of other factors. But because it is a third-order it is very hard to measure the impact of policy, because:

* They are 'arms length' from policy changes.

* The indexes are slow to respond to changes.

* They are noisy and affected by unrelated factors (i.e. does a colder winter decrease happiness?)

* A policy which improves well-being today could very well decrease well-being far into the future (e.g. increasing a countries spending and decreasing tax).