I'm working in a textile company that have stores in many countries.While planning quantities of product,we are considering of product display capacity.Every product taking up 1 exhibition space.For must requested products,we are taking up more than 1 place.So we are keeping the depth of the stock for the product.Let's say we planned the product with depth stock and sales has been ocured.We need to get referance this product and make plan on next year.We need to correct past sales values with find a parameter like "1 unit depth has %x effect on sales".Sales effecting by many factor like seasonality,price/discount,special period(holiday etc),customer entrance.Which statical method should I use in his context?Is there a way that I can implement in R Studio?