Market income is of interest as the definitional sum of factor incomes; it is also closer to factor shares in national income.
The first two categories correspond fairly closely to their counterparts in national income.
The first, RDI, is unproblematic, apart from the inclusion for consistency of imputed rents on owner-occupied housing in household income as well as national income.
Biases in the measurement of household income mean that national income shares must be kept in view when analysing the links between factor shares and inequality, as they are free from bias on those scores.
Second,to what extent are trends in factor shares in national income mirrored by those in household income?
In particular, the employment share in household income shows no equivalent to the rapid rise in its national income share during the downturns of 1979-80 and 1989-91.
By 1994 no counterpart in household income had yet emerged to the rapid rise in the investment-related share in national income during the previous 2 years - although the omission of capital gains is partly responsible for the absence of such a counterpart in income, as measured here.
The decline in the employment share since the late 1970s has been no less strong in household than in national income.