Excel Auto-Graphing

I am a beginner to formatting and programming with excel. I have made a file of which would automatically calculate my average grade for all of my classes. I was wondering if there could be a way to automatically graph this information. Every day that passes without update in current time, excel graphs the current grades. When the grades change, excel graphs the new changes. I have attached a file for reference to my excel file. I suppose one could make a macro (I don't know the language for Microsoft Macros) using this logic?
If current date > last updated date{
add new graph point for all grades with current date
}
else if grade =! previous grade{
add new graph point for specified grade
}
The grade would be any of the grades compiled from the specific grades in each class category.
Thanks for your support!
wwb00

Bonus- Can you simplify the code for the Bio and the Fre II Categories. I had to make code to multiply each value in each column which was not very efficient.