One of the basic motives for saving is the accumulation of wealth to insure future welfare. Both introspection and extant research on consumption insurance find that people face substantial risks that they do not fairly pool. In theory, the consumption and wealth accumulation of price-taking households in an economy with incomplete markets differs substantially from the behavior of these same households in the equivalent economy with complete-markets. The question we address in this article is whether we find this difference to be large in practice. What is the empirical importance of precautionary saving? We provide a simple decomposition that characterizes the importance of precautionary saving in the U.S. economy. We use this decomposition as an organizing framework to present four main findings: (a) the concavity of the consumption policy rule, (b) the importance of precautionary saving for life-cycle saving and wealth accumulation, (c) the contribution of changes in risk to fluctuations in aggregate consumption and (d) the significant impact of incomplete markets on aggregate fluctuations in calibrated general equilibrium models. We conclude with directions for future research.

We argue that the U.S. personal saving rate’s long stability (from the 1960s through the early 1980s), subsequent steady decline (1980s - 2007), and recent substantial increase (2008 - 2011) can all be interpreted using a parsimonious ‘buffer stock’ model of optimal consumption in the presence of labor income uncertainty and credit constraints. Saving in the model is affected by the gap between ‘target’ and actual wealth, with the target wealth determined by credit conditions and uncertainty. An estimated structural version of the model suggests that increased credit availability accounts for most of the saving rate’s long-term decline, while fluctuations in net wealth and uncertainty capture the bulk of the business-cycle variation.

Our estimates indicate that 24% of net wealth is attributed to precautionary savings in Australia. Moreover, across the income distribution, we find that low-income households have the highest fraction of their wealth accumulation explained by precautionary motives. These results for Australia are at odds with the estimates of precautionary wealth in the United States where related studies find that low-income households hold low levels of precautionary savings. Using a simple theoretical model, we show that differences in means-tested social insurance programs can rationalize these large differences in our empirical results.