I've been observing for a while how many investors skip a crucial step before putting money into a company: truly understanding its financial health. And this is where something that banks and professional analysts constantly use comes into play: the guarantee ratio.

This indicator is quite different from others you might have heard of. While some ratios show you if a company can pay its short-term debts, the guarantee ratio gives you the full picture. It tells us whether that company has enough assets to cover all its debt, no matter when it matures. The fundamental question is: if everything collapsed, could this company pay what it owes?

The formula is simple. Divide total assets by total liabilities. That's all. You don't need to be an accountant to understand it. If you take the balance sheet of any company and apply this calculation, you get a number that tells you a lot about its stability.

Now, what does that number mean? Here's where most people get lost. A guarantee ratio below 1.5 is a red flag. It means the company is too leveraged, has too much debt, and is at risk of bankruptcy. Between 1.5 and 2.5 is what we consider normal, the range where most healthy companies operate. Above 2.5, it could indicate they are underutilizing their borrowing capacity or have too many idle assets.

Let's take Tesla. Recently, it had a guarantee ratio around 2.26. Sounds high, right? But for a tech company, that makes sense. They need a lot of capital for research and development, and prefer to finance themselves with equity rather than debt. That’s strategy, not weakness.

Then there's Boeing. Its ratio dropped to 0.89, meaning its liabilities exceeded its assets. This didn't happen out of nowhere. When COVID hit, airplane demand plummeted and liabilities multiplied. The guarantee ratio perfectly captured that crisis.

The important thing is not to obsess over a single metric. The guarantee ratio works best when combined with the company's history, industry context, and other indicators. Revlon is the extreme example: its guarantee ratio was just 0.50 before declaring bankruptcy. Assets were $5.02 billion, but liabilities reached $2.52 billion. The math was clear.

A real advantage of the guarantee ratio is that it works equally well for large and small companies. It doesn't discriminate by size. And it's accessible—you can get it directly from the balance sheet without complex calculations.

The conclusion I've seen after analyzing several cases is that this ratio rarely fails. All companies that went bankrupt previously showed a compromised guarantee ratio. If you use it together with short-term liquidity analysis, you get a pretty clear picture of any company's financial health. It's a valuable tool that many investors underestimate.