Invoice design challange

[JohnUgoji]

Can I get help. I am just working on an invoice. I have successfully created it with price field in the product table so that once I choose the product on the line item I get the price loaded. But I discover that once there is a price change, the value on the totals change for that particular item.
What do I do in order that price changes does not affect the reports. Do I have to have another table?
Someone help me please.
Joh

 

[boblarson]

In one of your tables, I will just say Invoice table, you need to store the price. That is one item that is okay to store again as it can change.