Before we deal with individual prophylactic preoperative tests. Let's take an example and see what the costs are. Let's try using persantine thallium. Persantine thallium costs somewhere in the range of $1,500. If you applied it to the six million (6,000,000) patients with either known coronary artery disease, peripheral vascular disease, or two risk factors for coronary artery disease which include (age greater than or equal to 65, hypertension, smoking, hyperlipidemia, or diabetes) it would cost $9,000,000,000 ($9 billion) dollars a year. Thirty seven percent would be positive. You then buy two million angiograms but a CABG at $20,000+ per patient. For another $44 billion dollars. The persantine thalliums plus the CABG's run $53 billion dollars. Now if you are going to order 6 million Pthals, you may get a discount, but it is a big number. The perioperative risk is reduced by 50%, for the subsequent elective non-cardiac surgery. For a cost per life saved of $4.4 million dollars. But wait! CABG has a mortality of 3.2% in the U.S. Don't I have to add the risk of the CABG to the subsequent operation? Yes! We will get to that.