Interest payments plus amortisation of the private non-financial sector as a share of income. It measures how much of income goes to servicing debt at current rates.

Threshold source: Drehmann and Juselius (2012), BIS: a DSR one point above its own average has preceded banking crises. How thresholds are chosen

Assumes a standard maturity for all debt, so it moves with rates faster than actual household payments do.