Also note that you can use a different measure or calculation for color other than the text displayed. So, you could do something like the image below.
Note how the $279K value in the South column is darker green than the $315K in Central and even the $396K in West. That's because I've changed the SUM(Sales) on color to use a table calculation (right click the field, select "Quick Table Calculation" --> "Percent of Total", then right click again and select "Compute" --> "Table Down"). That way the color is light to dark based on the values in the columns instead of the overall table.
Great tip. Hope I can remember that one.
This is what I was looking for. I ended up using it by date using January as a baseline for the category spend over the year.