In one recent quarter, the fees accounted for fully a sixth - roughly $200 million - of Blockbuster's revenues.
At one bank, fees from checking-account customers last quarter accounted for $59 million.
Ms. Reif Cohen estimates that such fees will account for only $50 million in revenues this year.
Tuition and fees do not account for living expenses.
In the past, late fees had sometimes accounted for more than 15 percent of the company's quarterly revenue.
A year ago, in the quarter that ended June 30, 2000, late fees accounted for 16.7 percent of the company's revenue of $1.2 billion.
Late fees had accounted for roughly 14.3 percent of Blockbuster's $3.3 billion in revenue for the first nine months of 2004.
In the same period in 2005, those fees accounted for just 2.2 percent of rental revenue.
But today, rental fees account for most of the company's revenues.
If that is so, the fees accounted for more than half of Marsh's net income of $1.5 billion last year.