Simple Average percent calculation

Hi

 I have 5 inputs arriving on a results page. From these results I am wanting to calculate an average percentage.

 From these I want to display the average of all these (Bottom Box) I have read lots on the forums about how to do this but I do not want a button press or anything else, I just want it to display the result. I thought this would be so simple but I cannot work out how to so this.

 Thank you anyone for any help or support on this simple matter (I hope)

 Rich