Is there a way to save daily summary report numbers into a table to create a daily history of a report total? I want to see things like pipeline size over time.

You could skip all that of copying things from one table to another, by using a date field in your pipeline to categorize / sort the resulting data.  

It seems like a lot of extra steps if you just want it "so I can see a day by day history of the data to establish trends."  It give you a lot more future options to keep the data together.