Clarified Auditing Standards require quantification of materiality levels, which are estimates to guide auditors' decision-making and design of auditing procedures. This estimate is only a guide and is not a specific determination of what is, and is not, material in an audit.
1 The current population of the United States of America is 324,385,585 as of Friday, August 12, 2016, based on the latest United Nations estimates.  the United States population is equivalent to 4.38% of the total world population.
US Population to Hit 324 Million in 2016, 400 Million in 2050. The U.S. population is aging, and is moving away from one which is largely descended from people who came from Europe and more toward people from Central America, Mexico, and Asia. And, the rate at which the U.S population is growing has stagnated. There will be 323,996,000 Americans in 2016, barely up from 321,369,000 last year and slightly less than 326,626,000 in 2017. The U.S. population will not reach over 400,000,000 until 2051, when the Census forecasts it will reach 400,124,000.