It varies by pool size. A typical 2 ppm FC per day for 23,000 gallons would require around 3/4-gallon (so a 96-ounce jug) of 6% bleach per day. Prices vary but are usually in the neighborhood of $1.30, sometimes less. So that would be about $40 per month for your pool. Chlorine usage varies, but is usually in the 1.5 to 2.5 ppm FC per day range. If your pool is exposed to a lot of sunlight and you are seeing higher chlorine demand well above 2 ppm FC per day, then a higher CYA level (with a higher proportionate FC level) can lower your chlorine usage (or perhaps you need to shock your pool to get rid of nascent algae growth). Use of a mostly opaque pool cover really cuts down usage which is why in my pool the usage is less than 1 ppm FC per day which for 16,000 gallons comes to around $15 per month with the pool used (open) for 1-2 hours every day.