Different Consumption Responses to Equivalent Changes in the Real Interest Rate

We study how individuals adjust consumption in response to changes in the real interest rate using a large, preregistered, within-subject survey experiment on a representative sample of the German population. Respondents evaluate hypothetical scenarios in which the real interest rate rises by five percentage points through either an increase in the nominal interest rate or an equivalent decline in inflation. While classic intertemporal choice models predict identical responses across these scenarios, we find a clear asymmetry: respondents plan sizable cuts in consumption, higher saving, and lower borrowing when nominal rates increase, yet adjust these margins much less when inflation falls. Differences in perceived wealth effects may contribute to this asymmetry, but they cannot fully explain it. Rising nominal interest rates appear to provide stronger incentives to increase saving and avoid borrowing than does declining inflation. Declining inflation is also associated with more contradictory choices, for example, reporting higher consumption and higher saving while leaving borrowing unchanged. Together, these findings suggest that respondents more readily internalize the consequences of nominal interest rate changes than of disinflation, which has implications for the design and communication of monetary policy.