I am keeping an account in a spreadsheet of how much time I meditate as well as the cumulative debt in hours relative to an ideal minimum amount of 32 hours per week. If the debt is building up then I need to cut back on other commitments to make sure that the debt is being reduced, and ultimately becomes negative (a credit surplus).
The weekly minimum amount is based on meditating at least 1.5 hours in the morning, at least half an hour at midday, and at least 2 hours at night, and a weekly long meditation of at least 6 hours.
While it may be useful to keep an eye on how much time I meditate, what is more important is to make sure that I make a spiritual effort more, as Sri Yukteswar said. It can also become impractical to be too focused on “paying back” debt to the detriment of a life balance. But the meditation debt can help to act as an indicator of imbalance and be a signal to rectify the situation.