The ratio of shortage cost 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 Online Accounting equals the daily standard deviation of demand times the square root of the lead time. The probability is 95 percent that demand during lead time will not exceed the amount on hand at the beginning Bookkeeping for Veterinarians of lead which one of these would not be a factor in determining the reorder point? time.