This brief assesses where we have been and where we are going regarding the nation’s population and its associated potential workforce. This workforce provides the commuters. In general, demographic change moves at a slow and predictable pace. Earlier editions of Commuting in America found that starting in about 1950, the nation added roughly 25 million persons per decade; the census projections of that period indicated that it would be a relatively safe estimate for the future going out another 50 years. Figure 3-1 shows that today, such an assumption is under challenge. The data show far more volatility in the actual census counts in the past two decades. The 1990s exhibited an unexpected surge in population beyond Census Bureau projections due to a boom in immigrants and high immigrant fertility. The 2000s saw a sharp reversal in those same patterns, with a population increase similar to that of the 1950–1960 decade. More recently, changes in both immigration and fertility rates have led demographers to moderate future forecasts to below the approximate 1 percent per year or 30 million new residents per decade growth seen in the recent past.