What is the "Savings" amount at the upper right on the budget page?

Flutes

I see an extra $20 at the bottom of each month in the budget annual view. Where did this come from come and how do I set it to zero?

Sherlock

Savings is the amount by which the allocated income exceeds the allocated spending.  

The bottom of the annual view are Totals (aka a sum).  Depending on which column you're viewing, you would need adjust the budget allocations or the actual spending appropriately if you want a total amount to be zero.