I am looking at sovereign debt as a percentage of GDP. However, due to external factors like exchange rates, the percentage may change from one year to the next even if a government did not borrow any money at all. I am therefore looking for an indicator that measures how much money a government has borrowed, rather than debt in terms of GDP.
Context: The economic policy of Mexico's president boils down to cutting expenditure and freezing public debt. Even though no new debt has been contracted, the percentage of sovereign debt in terms of GDP recently reached an all time high. I would like to separate the effects of interest rates, exchange rates and the recession from the amount of money borrowed by the Mexican government (which technically should be zero).