Excel can be used to create most graphics. It can be a bit click-y, but for one-off graphics, Excel is often the fastest way to create a custom graphic if you already know how to use it. The trick is to not accept Excel's defaults, so it doesn't look like out-of-the-box Excel junk that can be spotted from a mile away.
The one below was created in about 15 minutes (including making up data):
