I don't no. I ran my last boat for 25 years (a custom built Bruno-Stillman) Made good money with her over the years and finally sold her for $30,000 more then what I paid for her. Lucky for me that was 3 months before the cost of diesel went from $1.00 a gallon to $3.00 a gallon but who knew?
Now fully retired for 9 years I have the time to clean my 16 footer. The cost of gas is negligible but the cost of libation while cleaning keeps going up.
But who needs money when you don't have to drive to work every morning and you like eating fish?