For US CP, 100% bonus miles is only for flights > 1000 miles. All bonus miles for flights < 500 miles are calculated by adding bonus miles until the actual miles + bonus miles = 1000 miles. Full fare flights < 500 miles have bonus miles added until the total = 1250. Flights > 500 miles but < 1000 miles get 150% bonus. In 1999, AA for PM is + bonus to equal 1000 miles, 100% bonus if > 500 miles, and no full fare bonus.