The fourth and parallel transformation in social structure has been in terms of changes in living arrangements, that is, shifts in the ways that we choose to construct (or deconstruct) households and families, and the lifestyles and attitudes associated with these shifts. This transformation has also been of fundamental importance, but its effects are often underestimated. It should be stressed that the process of household formation defines the units of collective consumption, as in the case of housing, and the units that shape income distributions and anchor individual links to urban labour markets. While it is individuals who work and earn income, it tends to be households that spend that income and make the major decisions about consumption of housing and other goods, as well as about residential and workplace location.
The shifts in the nature and composition of households and families have been equally dramatic. Families have been redefined, reflecting a wide variety of factors: changes in fertility levels, higher income levels, more flexible social practices (such as living alone or same-sex marriages), revised public policies (such as those on divorce), and changes in attitudes and lifestyles. In parallel, average household size in Ontario has shrunk over the postwar period from over 4.0 persons per household in the 1950s and 1960s to under 2.7 in 2001. This represents a decline of roughly 30% in average household size. In the older parts of the Toronto region, the average household size is now under 2.1, and in the central core it is below 1.5 persons. Fewer children per family, more non-family households (now 30% of the total), more single-parent households, and more single people living alone, especially among the young and the elderly, have all contributed to this shrinkage and therefore to fragmentation of the units of collective consumption, increased income inequalities, and the diversification of housing demand.
These trends have also changed the linkages between households and the world of work. For example, there are now, on average, fewer workers per household. The most rapid increase has been in households with no workers in the labour force - the unemployed, single parents, retired households, and those not otherwise in the labour force. There has also been a relative decline in those households with one worker, an increase in those with two workers, and a decline in the proportion of multi-worker households. These shifts have immense implications for the distribution of income from employment, and the rise in the incidence of poverty.
This decline in household size, in turn, has resulted in a corresponding increase in the number of dwelling units, land area, and capital investment required to house an equivalent number of people. This downsizing alone, by my own calculations, accounts for almost half of the growth in aggregate housing demand. It has also accounted for the majority of the decline in population densities in established urban neighbourhoods, a process known as demographic thinning. 10 Such density declines, often cited in the planning literature as a cause of concern, are in this instance a direct result of demographic change and rising incomes.