What is this?
This graph shows how much revenue (money in) and expenses (money out) the charity has had each year over the last few years. Charities have many sources of revenue, such as donations, government grants, and services they sell to the public. Similarly, expenses are everything that allows the charity to run, from paying staff to rent.
What should I be looking for?
First off, this graph gives a general indication of how big the charity is - charities range in size from tiny (budgets of less than $100,000) to enormous (budgets more than $100 million). You're also looking for variability - if the charity's revenue and expenses are jumping up and down from year to year, make sure there's a good reason for it.
Unlike companies, charities and not-for-profits aren't on a mission to make money. However, if they spend more than they receive, eventually they will go into too much debt and run into trouble. As a very general rule, you want revenue to be slightly above expenses. If expenses is reliably above revenue, the charity is losing money. If revenue is much larger than expenses, it means the charity might not be using its resources effectively. It isn't always that simple, however, and there's a lot of reasons a charity might not follow this pattern. They might be saving up for a big purchase or campaign, or they might have made a big one-off payment. If you're worried, always look at the annual and financial reports to understand why the charity is making the decisions it is.