There's another way, maybe not the canonical way, but I've written a python script for my own booking website (https://bookings.beatthatflight.com.au/)my own booking website that can go through every date of the year for a given city/hotel, and find the best price/discount.
So if you're a coder, you could do something like that.
Many booking sites also have an API for coders (eg Skyscanner: https://rapidapi.com/blog/skyscanner-api-overview/Skyscanner) and you could potentially write code against that as well to quickly get a list of prices.