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: worldstat.us construction after Drehmann and Juselius (2012), BIS, who found the DSR well above its long-run average before banking crises; one point is far tighter than the deviations they report. How thresholds are chosen
Assumes a standard maturity for all debt, so it moves with rates faster than actual household payments do.