The greater variation in the data at higher levels of mean living standards can also be seen to reflect greater variation in the social subjectivity of poverty lines at higher levels of development. Indeed, the political nature by which societies choose to set their national lines may become more salient at higher levels of economic (and institutional) development. A tendency for higher income countries to politically decide to choose a higher poverty line than what might otherwise be the most socially salient poverty line would bias upward the regressions on which Ravallion and Chen's income elasticity of the poverty line is based. Citing Fuchs (1969), he reminds us that it is desirable for the setting of the poverty line to be recognised as "a national value judgement-arrived at through the normal political process".