The calculator roughly calculates some of the most important metrics in business. Such as - the cost of registration, the cost of a subscriber, the time until the first money, how much money is needed to start, what advertising costs are needed.
This is the ideal model in which all indicators are stable from month to month. In reality, each month will be different from the previous one. Usually, the changes are not so significant, and this does not prevent you from using the calculator result as a guideline to which you can strive for the growth of your business.