Will adding unit prices after a sale, add that unit price to the past sales or just moving forward?

[MorchellaMarket]

I had many items in my inventory without unit prices. I've since added them, but we have been operational for 8 months. I am concerned my COGs is going to be incorrect up until now. TIA

[JJ_]

This may definitely affect your COGS but to better explain how I would recommend reaching out to our Retail team by login into your account and going here. They would be able to answer specific questions regarding your Cost of Goods Sold report.