How do you figure out your prices?

We do thousands of jobs each year. Each job listed in the price book has a history behind it. We have time and material statistics for every job that we have done since 1968. To compute a job rate, we take the average time and material for that job and use that data in conjunction with all of our other costs of doing business to calculate a final price using a pricing matrix. We review our prices each year and adjust them if necessary.