The article examines how much money creditors lose when borrowers default on their residential mortgages. Researchers created a new method to estimate these losses by looking at factors like the likelihood of default, the value of the property, and the remaining loan amount. They studied data from Russian government mortgage loans and found that the amount lost in a default can vary widely. Loans with high levels of borrowed money tend to result in higher losses for creditors. The study also suggests that mortgage insurance can help offset these losses. Overall, the research shows that the risk of losing money on mortgage loans increases when legal costs for settling debts go up.