Each transaction listed in the customer's activity log has a date and time, the balance (amount of the top-up, for example), balance used (out of this particular top-up) and remaining balance (if part of this top-up is used, the balance will be positive, but if the whole top-up is used up, then the remaining balance is zero).

Please note the activity log lists not the entire wallet balance as in the general info section of the customer's profile, but a balance of each top-up, bonus etc.