Tightening cycles amplify policy impact as debt burdens rise

Using a smooth-transition local projection model for the euro area from 2001 to 2019, the study shows that monetary transmission strengthens during periods of elevated financial exposure.

When the debt-service ratio is high, a one-standard-deviation rate shock reduces output and inflation by 1.3 percent at peak, more than four times the output decline under low exposure.

In a simulated one-percentage-point tightening across four quarters, the debt-service ratio rises by 45 basis points, making subsequent rate increases 22 basis points more contractionary than after a loosening cycle.

A steeper four-percentage-point tightening accelerates this amplification across the economy.

Macroeconomic conditions dictate transmission.

When tightening coincides with a recession, debt-service ratios rise by 64 basis points, driving peak output losses to 5.0 percent and amplifying rate potency.

In contrast, economic expansions generate nominal income growth that offsets rising debt costs, keeping policy effectiveness stable.

Tightening cycles also leave the economy four times more vulnerable to real estate shocks: a 40-basis-point drop in house prices triggers a 45-basis-point inflation decline, compared to 16 basis points following a loosening.