The cost of living in Washington, D.C., is also higher than the national average, ranking fifth among the most expensive U.S. cities in Numbeo’s cost of living index (5).Considering that the median earnings of an American worker in the 45-54 age range is $71,552 — or $67,704 for those in the 55-64 age range, based on data from the U.S. Bureau of Labor Statistics — Trias and his wife are essentially saving the equivalent of a single American worker’s annual salary every year (4).There are four specific areas ...