Total Debt Service Ratio - TDS

See: Times Interest Covered.

"Debt Service" comprises the interest the borrower is paying plus the principal paydown, plus any other add-on costs, like loan insurance. (See: Private Mortgage Insurance - PMI.)

So that's the numerator. What goes in the denominator? Like, what's the ratio here? Debt service cost to...what?

Cash flow. The whole goal in finding this metrical calculation is to figure out how safe the company's debt payments are. So like...if its total debt service or cost to pay all of its debt or debt-like obligations (including things like committed leases on buildings or equipment) is, say, $40 million a year, and its cash flow is $150 million, then all's fine in the world. The company has waaaaay more than enough cash to service its debt or debt-like obligations, and the CFO can sleep like a baby at night. Or...however she likes to sleep.