What percent of habits are housed in and carried out in response to cellular memory?

This is well over 90% and the reason for the vagaries in number are the loose definition in assigning the term, "habit," to behavior. It is not always easy to discern when something becomes a habit and when it is simply learned behavior that is turned to in the moment out of convenience and is a well-worn path in the experience and knowledge base called upon to add efficiency to the operation. Habits, on the other hand, are more automatic, triggered from within, secondary to conscious thought and desire. They may be reawakened by perceiving something in the environment as a cue, such as seeing the day of the week it is on the calendar or the time of day, and so forth. People differ in how they structure their time and establish their routines, but the key in a true habit is it will rise from within and, even if neglected or overlooked for a time, will become a compulsion at some point through reminders by the subconscious that the habit is being neglected and will become more and more an imperative. So this is one of the primary ways in which cellular memory serves the individual because habitual behaviors are quite beneficial as an asset in making one’s actions highly efficient and requiring much less mental focus and energy in their execution because they can be done readily and seem almost effortless. That is the benefit of repetition and creating a repetitive operation that is desirable but done in a very similar way each time and that favors the well-worn path that happens almost on its own. This conserves energy and leaves the brain free much more of the time to be creative in other ways and let things unfold once decided on through largely a memory process and this is highly beneficial.