There really is no short or simple answer for that. Any number of factors can affect it, tap value, footage from the active, system bandwidth, mainline passives, type of channel (analog or digital) etc. all legacy charter should be all digital, other than carriers for pilot channels but the bright house and time warner systems may still have analog. IF it is an all digital channel lineup, you shouldn't have anything above 24db or below 7db give or take a few for inherent differences and fluctuations in the system and the occasional silly design. Analog will be approximately 6db higher than that but if you're in a charter system that still has analog channels, it won't for long.
This is CABL.com posting #372508. Tiny Link: cabl.co/mbI4m