It's not a useless measure. Normalizing total debt against total income is a sensible way to compare countries to another. It's just not a measure that is a uni

It's not a useless measure. Normalizing total debt against total income is a sensible way to compare countries to another. It's just not a measure that is a unitless ratio of two measures with the same units. (The unit is years [of income to payoff the debt if no further interest accrued].)