Re: How many remaining?

Posted by BigKev On 2013/12/25 18:25:08

I like to use a 5% per year decay rate of cars to figure out how many are left in the general sense (running, part cars, etc). Obviously high-dollar and speciality cars are better taken care of, so may not apply (ie Carribeans).

So for example:

If a particular car was made in 1955, and 10,000 units were produced, then by 1956, figure 500 of those 10,000 units would be off the road due to accident, mechanical, theft or other issues. So that leaved 9,500 units.

So in 1957, we apply the 5% rule again. So out of the 9,500 units remaining, and we are left with 9,025 units (475 gone).


So in 1958, we apply the 5% rule again. So out of the 9,025 units remaining, and we are left with 8574 units (rounded up), 451 gone.

So every year until the present, we take the remaining units and multiple by 95% to get the remaining, and keep repeating until we reach the present year. Even though we are still applying the 5% rule, yearly attrition rate get smaller it is calculated based on the number of surviving cars from the previous year.

Why not perfect, it will get you a ballpark estimate of the remaining cars still out there (running, and part cars).