Calculation of one average in PPT and format shape

I am helping a client's client put together a simple balanced scorecard in powerpoint (not the best choice of tool if you ask me, but what can you do...). I need to - Calculate and display an average number based on four fields (for some reason I can't get VBA to calculate and display the average?!?) - Change the color of one element in the powerpoint based on the average I will probably need more help on this, but this is a start. Please use no extensions, only VBA. Please comment your code.