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Debt Service Coverage Ratio (DSCR)

Debt Service Coverage Ratio formula, calculation and typical ratios across industries.

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Debt Service Coverage Ratio Formula (DSCR)

The debt service coverage ratio (DSCR) formula is as follows.

  • DSCR = Cash Flow Available for Debt Service  / Debt Service


  • Debt Service = Principal + Interest

Unlike corporate finance, in project finance lenders are paid back solely through the cash flows generated by the project (CFADS) and DSCR functions as a barometer of health of those cash-flows. It measures, in a given quarter or 6 month period,  the number of times that the CFADS pays the debt service (principal + interest) in that period.

DSCR Role in Project Finance

The DSCR is used for two main purposes in project finance: Sculpting & Debt sizing and Covenant testing.

1. Sculpting and Debt Sizing

This is used prior to financial close, in order to determine the debt size, and the principal repayment schedule.

Lenders will set debt sizing parameters, typically including a gearing (or leverage) ratio (Loan to Cost Ratio) and a DSCR (sometimes a LLCR in addition to, or instead of, a DSCR). While the gearing ratio helps to ensure that equity have skin in the game, the DSCR target ratio helps to ensure that a minimum DSCR is maintained at all times.

Here the formula is rearranged, and the debt service is calculated based off the forecast CFADS and specified DSCR.

Debt service = CFADS / DSCR

The debt service can be thus calculated in every period to satisfy the lenders sizing parameters. Sculpting the debt service based off the CFADS and target debt service will yield a debt service profile that follows the CFADS (as above).

Upon adding all the principal components of the debt service up, that will calculate the debt size. Learn more about debt sizing here and learn to build macros automate the process here.

2. Covenant Testing

As the loan is getting repaid during the operations phase of a project, covenants are set in terms of maintaining minimum DSCRs. There are two covenants to pay attention to

  • Lock-up: DSCRs form a part of the lock-up covenants. For example if cash-flows breach a minimum covenant of 1.10x, this may trigger a project lock-up. There are different restrictions that this may trigger but the main one is a restriction of distributions to equity holders.
  • Default: If the DSCR is less than 1.00x, that means that the project cashflows are not sufficient to meet the projects debt service obligations. Per the facility agreement, this would constitute a project default, which means that the lender has step in rights; and can run the project in their best interests.

The function of these covenants is to give lenders some control, providing a mechanism through which to bring the project sponsors to the table to re-negotiate.

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In period vs annual ratio

The DSCR can be expressed as both an “in-period” or an annual ratio. The project term sheet will specify how covenants are calculated. As it can fluctuate from period to period, covenants may be defined annually via a LTM (last twelve months) or NTM (next twelve months) summation.

Minimum vs. Average DSCR

The minimum DSCR is usually pulled out of the model to be presented on summaries – this helps to identify a period of weak cashflows and when it occurs.

The average DSCR is a useful overall metric to understand how many times the total CFADS during the debt tenor covers the debt service. While a useful metric to have, it is less sophisticated than the LLCR, which takes into account the timing of cashflows through discounting

DSCRs increase with volatility in cash-flows

If the future was perfectly known and the CFADS forecast exactly equaled the CFADS generated then the debt service could theoretically be set at exactly equal to the CFADS (in other words the DSCR could be 1.00x).

That’s because the lender would be certain to be paid back in every quarter.

Of course this is theoretical and wouldn’t be favorable to equity investors, who are incented to get distributions as soon as possible (with a cost of equity higher than the cost of debt).

The greater the uncertainty in cash-flows (CFADS), the higher the buffer between CFADS and debt service. Thus the the riskier the project, the higher the DSCR.

DSCR By Industry: Sector Benchmarks

The below DSCRs are indicative only, as each project will vary. Different industries have different risk profiles, and thus different DSCRs.

Project Sector Average DSCR
Water (regulated) 1.20x-1.30x
Wind farm 1.30x-1.50x
Telecom 1.35x-1.50x
Water with offtaker 1.50x-1.70x
Power with no offtaker 2.00x-2.50x
  • Projects with low DSCR: Projects that have no demand risk will have a low DSCR, like an availability based toll road (i.e. the SPV is paid based on having the road available and meeting certain conditions, rather than the level of traffic).  Another example might be a regulated water utility, which due to stable incomes will have a low DSCR.
  • Projects with high DSCR: A power generator, on the other hand, is exposed to fluctuations of electricity prices. Throw in no counter party with a contracted requirement to take the power, and the project is truly at the mercy of the markets. As a result, the project would carry a higher DSCR.
By Kyle Chaning Pearce
Kyle is a financial modeling instructor/practitioner with years of experience of project finance modeling training at Investment Banks, Funds, Project Developers, Big 4 Accountancy firms and more. Kyle was previously head of training EMEA at Mazars Global Infrastructure Finance, and trained professionals and students in project finance financial modeling around the world with project finance consulting firm Corality.
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