GDP and standard of living

World GDP per capita changed very little for most of human history before the industrial revolution. (Note the empty areas mean no data, not very low levels. There are data for the years 1, 1000, 1500, 1600, 1700, 1820, 1900, and 2003.)
GDP per capita is often used as an indicator of standard of living in an economy. While this approach has advantages, many criticisms of GDP focus on its use as a sole indicator of standard of living.
The major advantages to using GDP per capita as an indicator of standard of living are that it is measured frequently, widely and consistently; frequently in that most countries provide information on GDP on a quarterly basis (which allows a user to spot trends more quickly), widely in that some measure of GDP is available for practically every country in the world (allowing crude comparisons between the standard of living in different countries), and consistently in that the technical definitions used within GDP are relatively consistent between countries, and so there can be confidence that the same thing is being measured in each country.
The major disadvantage of using GDP as an indicator of standard of living is that it is not, strictly speaking, a measure of standard of living. GDP is intended to be a measure of particular types of economic activity within a country. Nothing about the definition of GDP suggests that it is necessarily a measure of standard of living. For instance, in an extreme example, a country which exported 100 per cent of its production and imported nothing would still have a high GDP, but a very poor standard of living.
The argument in favour of using GDP is not that it is a good indicator of standard of living, but rather that (all other things being equal) standard of living tends to increase when GDP per capita increases. This makes GDP a proxy for standard of living, rather than a direct measure of it. GDP per capita can also be seen as a proxy of labor productivity. As the productivity of the workers increases, employers must compete for them by paying higher wages. Conversely, if productivity is low, then wages must be low or the businesses will not be able to make a profit.
There are a number of controversies about this use of GDP.