Don't mix text and numbers.
Another recommendation is to make sure your data is suitable for the diagram. For example, if you want amounts to show up properly as progress bars or meters, don't mix text with your numbers. Notice the CPU column in the table on the left. It contains only numbers. But the example on the right has a mix of text and numbers. If you mix text and numbers, the data will be treated as text, and the bar or meter won't show a quantity as you'd expect.
