Some Thoughts re Mankiw's Textbook Essay

Several weeks earlier, Gregory Mankiw reflected on his years spent in textbook authorship and teaching. The whole essay was quite interesting, and Scott Sumner also highlighted in an Econlog post a part I particularly liked. In this post I at least want to consider how savings decisions and market expectations matter for equilibrium outcomes. Output variance between non tradable and tradable sector activity, could also impact how investments affect aggregate output and demand. Nevertheless, here's Mankiw (page ten):

As a sign of how times have changed, imagine asking a group of introductory students the following question: If Americans decided to save a larger fraction of their income, how would this change affect the economy?  The answer I learned as a freshman in 1977, studying macroeconomics from Paul Samuelson's celebrated text, was based on the Keynesian cross and the paradox of thrift: Higher savings rates depress aggregate demand, reduce national income, and in the end fail to result in higher quantities of saving. By contrast, the first answer I teach as an instructor today is based on classical growth theory. Higher savings means more investment, a larger future capital stock, and a higher level of national income. Most economists now agree that both answers have some degree of truth, depending on the circumstance and that students need to learn both perspectives to understand and debate public policy.

Previously, savings as investment has been more likely to result in increased output during periods of manufacturing expansion. Yet it isn't difficult to imagine, how manufacturing losses during periods of extensive monetary tightening (such as the Great Depression) could seem as though depressed demand from higher savings. All the more so, when extensive depreciation further discourages spending. Fortunately, once manufacturers regain the confidence to increase output, savings are once again better able to translate into output gains, thereby returning to a long run trend or classical interpretation. Gregory Mankiw stressed that when long term economic conditions are emphasized at the outset, it's easier for the student to interpret Keynesian factors as short term fluctuations in trend.

One policy concern for macroeconomic issues, is the extent to which governments can meet existing near to medium term budgetary obligations. Clearly, there are links between equilibrium capacity and what governments might achieve, in terms of the revenue this capacity suggests. I found Mankiw's explanation for welfare economics helpful, for deliberating how societal expectations could alter what otherwise appears as producer and consumer surplus. Once specific markets become saturated, those limits tend to become part of general equilibrium constraints. It's not difficult to extrapolate how that creates limits for government revenue potential as well.

Market saturation may also vary, depending on whether what appears as natural limits is due to tradable sector or non tradable sector market capacity. Some portions of aggregate output in the latter, mostly scale according to time/place linked participation in consumption and production. When governments agree to additional restraints on non tradable sector activity, it becomes even more difficult for fiscal policy to stimulate demand. The resulting asymmetries in supply side production potential, add to other difficulties governments already experience, in gaining sufficient revenue for budgetary requirements.

Why does this matter? Government incentives to stimulate economic conditions are closely connected with what they hope to gain for their own support, via stable or increased revenue potential. A recent WSJ article, for instance, noted how the Trump budget could be relying in part on phantom revenues. But will the needed $1.2 trillion in the next decade, actually materialize?

Healthcare services - in spite of what they demand from governments - have become a source of government revenue in their own right. But what if consumer healthcare decisions change in the near future? If so, equilibrium capacity for healthcare markets as presently constructed, could be reduced. As healthcare spending continues to shift from insurance contributions toward increased out of pocket expenses, will consumers continue to perceive this approach to well being as totally necessary? Ultimately, increased consumer responsibility for all healthcare considerations, might include a reevaluation of overall healthcare spending.

If so, changes in healthcare market demand might eventually lead to changes in organizational capacity as well. Would a DIY approach for healthcare needs, become a part of reduced government expectations for revenue in the coming decade? It's certainly a possibility, and one which also speaks to the importance of welfare economics as noted by Mankiw.