Price report design – Showing normal price during active promo-only period

I have a report which shows pricing during a date range for products. The goal of the price list was to show the customer what they will be paying on any given date during the range we give.

However, here's my problem. There are periods which products are on promotion only or go from one promotion to another. We have to show the "normal" price for that promotion so the retailer can appropriately mark sales and price reductions--even though they wont be paying that price.

F = Normal price (F because it's abbreviating an industry term)

P = Promotion

Example of period where customer will only be paying promotion pricing, but needs to see the normal price:

Example where pricing transitions from promotion to normal to promotion:

Right now I'm using the three dashes to denote that "hey, you wont be paying this price but this is the normal price."

Any suggestions on a better way to denote that this is the normal price during that period? Such as a symbol instead of dashes?

Side-by-side normal and promotion is not really an option due to the report width and the fact some rows are not promotions. Additionally not possible because of how our pricing is structured.