There is no equation like this. However, most of the jobs today have a minimum degree requirements. Often times this means, any other degrees instead of BA is okay, but then experience should be applicable.
Often times, if you have a good knowledge and experience in a similar industry, don't worry about the number of years, apply and see what happens, if they call you and you really know your stuff, you will get the job.
Often times, if you have a good knowledge and experience in a similar industry, don't worry about the number of years, apply and see what happens, if they call you and you really know your stuff, you will get the job.