The ratio of shortage cost What is bookkeeping to shortage plus excess cost is 0.67. The ratio of shortage cost to shortage plus excess cost is 0.8. The ratio of shortage cost to shortage plus excess cost is 0.5. The standard deviation of demand during lead time equals the daily standard deviation of demand times the square root of the lead time. The probability is 95 percent that demand during Food Truck Accounting lead time will not exceed the amount on hand at the beginning of lead which one of these would not be a factor in determining the reorder point? time.