I agree with Karl, especially on his point about labeling the graph itself. In my office we are held to standards of good "chartsmanship" when preparing presentations, specifically using PowerPoint. When speaking, you might say: "The first graph shows an inverse relationship between interest rates and bond prices, while the second graph shows a proportional relationship between a company's credit rating and bond prices."

Hello, I am fine! Yes, what you've written is correct. There is such a thing as an Inversely Proportional relationship and there is a separate thing known as a Directly Proportional relationship. So you are using proper terminology. The only thing I would suggest is capitalizing the names the way I've done. This reinforces the idea that you're using a proper label for each graph.

Proportional relationship to what?