景気循環入門 III

GDP is used to measure business cycles, but it does not fully reflect economic performance.

So, economists often use a broader definition based on aggregate economic activity.

This approach combines measures such as GDP, employment, domestic investment, inflation, and other factors to provide a more comprehensive view of economic performance.

However, this approach also has its limitations.

First, there is no single rule for which measures to include. Inflation and investment are obvious choices. But should industrial production be included?

Consider a hypothetical economy that mainly produces services rather than goods. Would industrial production be a meaningful addition to an aggregate performance measure?

Finally, how should indicators be weighted? Is a one percent rise in GDP more important than a two percent rise in investment?

So, while more comprehensive, this approach is subjective. There’s no clear rule for which measures to include, or how much weight each indicator should carry.

Ultimately, some analyses rely on the simpler GDP-based definition, while others use aggregate economic activity.