Although airline schedules and cost are important factors for business travelers when choosing an airline carrier, a USA Today survey found that business travelers list an airlines frequent flyer program as the most important factor. From a sample of n=1993 business travelers who responded to the survey, 618 listed a frequent flyer program as the most important factor. What is the point estimate of the proportion of the population of business travelers who believe a frequent flyer program is the most important factor when choosing an airline carrier?