(Re-) Calculating Your Cash Burn Rate in a Downturn

So you started 2020 with everything figured out: you had a manageable cash burn rate, you had a clear amount of runway, you had a business strategy built around both. Then COVID-19 hit and everything changed.

So what do you do now?

There’s a number of steps that startups can take to manage their financial position in a downturn, but today we’re going to focus on the fundamentals: calculating your new burn rate and runway.

Calculating Burn Rate

The actual math for getting your burn rate is pretty straightforward: you subtract your cash balance at the end of the month from your cash balance at the beginning of the month, to get the amount by which your cash balance decreased. That amount is your burn rate. 

By examining your average monthly cash burn and its trajectory, you can estimate how much runway your company has to work with, i.e., how long you have until you run out of money (and we actually have a burn rate calculator to help you with this).

Calculate Your Burn Rate

The problem you’re likely facing now, of course, is that the numbers that went into those previous calculations are now changing significantly. While some segments are more affected than others, virtually all businesses are experiencing at least some impact from COVID-19. 

Getting Your New Numbers

It’s unfortunately safe to assume that in the next few months your revenue is likely to go down, and your customer churn is likely to go up. This translates to less income, which translates to a higher cash burn (assuming your expenses stay the same). And if your burn rate changes, your runway changes too. 

Updating your burn rate and runway means re-running your calculations with new numbers. To get those numbers, however, we have to take a step back. You need to have a solid model for making projections, so that you can factor in how revenue and churn and spend over time will impact your burn rate and runway. And to do that, you have to have clean books.

We’ve talked before about how clean books are crucial for making good business decisions (and no, we’re not just saying that because bookkeeping is our business). Your books are the ultimate source of truth for your company’s financial status – they tell you how much cash you have, what your assets and liabilities are, and where your company’s money is going. If you can’t trust the accuracy of your books, then you can’t be sure that your financial decisions are based on reality. In the current economic climate, this is more important than ever. Best-guessing your financials is a boom-market luxury.

Estimating Your New Runway

When you’re confident your books are accurate, you can pull the numbers you need to re-run your financial models. Use these to get new revenue and churn predictions based on the current market, which then gives you a new projection for how much cash you’re likely to bring in. Finally, use that cash projection vs. your expected expenses to recalculate what your burn rate is likely to be for the next months or year.

Given the current uncertainty around the pandemic and the markets, you should consider running numbers for multiple scenarios. What might your numbers be in a month if the situation continues to deteriorate? What might they be if it stabilizes? This is where it helps to do a sensitivity report for your current models. Here’s a simple example for a company with $100,000 cash in the bank and $10,000 in monthly expenses, examining how its cash burn and runway change with different levels of revenue.

Monthly RevenueBurn RateRunway
Current Revenue$4000$600016 Months
-10% Revenue$3600$640015 Months
-25% Revenue$3000$700014 Months
-50% Revenue$2000$800012 Months
-75% Revenue$1000$900011 Months

Doing this kind of analysis upfront helps you plan for what situations you might face, so you aren’t caught off-guard if the market continues to shift. Regardless of what the economy means for your original plans, you’ll be in a position to start making decisions about what your business needs now.