Nohing that will add anything to the current conversation, but just a thought that came to me. It might be useful to add a column to the chart with your actual bike expenses (that you could add to as you have new ones). then you could put in a calculation to divide your total bike related costs by the miles ridden to see your total cost per mile (however you choose to define it). In fact, that sounds like something I might do this evening. In addition to knowing the savings versus the car, it would be kind of cool to watch that # decrease (hopefully) over time as the miles add up.