Attracting and retaining people to live, work, raise a family, and retire underlies the economic vitality of any region. Population growth is both a cause--and a consequence--of economic growth. Patterns of population growth and change reflect differences among regions to attract and retain people both as producers and consumers in their economy.

The following graphs offer a broad overview of trends in the pattern of population growth and change of San Mateo County with comparisons to California and the nation at large. This analysis features alternative approaches toward discussing, diagnosing and comparing San Mateo County vs. California's population growth over 1969-2021. The data used are those compiled by the Regional Income and Product Divisions of the Bureau of Economic Analysis, U.S. Department of Commerce.

Figure 1 traces San Mateo County's annual population for the period 1969-2021 to illustrate population patterns over time. During this 53-year period, San Mateo County's population rose from 552,230 in 1969 to 737,888 in 2021, for a net gain of 185,658, or 33.62%.

NOTE: The county and state population totals reported by the Bureau of Economic Analysis (BEA) are from the Bureau of Census midyear (July 1) estimates. These estimates may differ from those prepared independently in some states by various agencies and/or universities.

Figure 2 traces California's annual population for the period 1969-2021 to illustrate population patterns over time. During this 53-year period, California's population rose from 19,711,000 in 1969 to 39,237,836 in 2021, for a net gain of 19,526,836, or 99.07%.

NOTE: The county and state population totals reported by the Bureau of Economic Analysis (BEA) are from the Bureau of Census midyear (July 1) estimates. These estimates may differ from those prepared independently in some states by various agencies and/or universities.

Figure 3 portrays San Mateo County's population growth in a broader context by offering direct comparisons across time with California, the United States. The growth indices shown here express each region's population in 1969 as a base figure of 100, and the populations in later years as a percentage of the 1969 base figure. This method allows for more direct comparison of differences in population growth between regions that may differ vastly in size.

San Mateo County's overall population growth was 33.62% over 1969-2021 trailed California's increase of 99.07%, and fell below the United States' increase of 64.88%.

Another interesting and insightful way of highlighting the population growth of San Mateo County is to trace its individual percentage contributions to California's statewide population over time, as shown in Figure 4. A rising share means a region's population grew faster, or declined less, than California's population, while a declining share shows it grew more slowly.

In 1969, San Mateo County's population totaled 2.80% of California's population, while in 2021 it totaled 1.88% thereby yielding a -0.92% share-shift.

Figure 5 highlights the short-run pattern of San Mateo County's population growth by tracking the year-to-year percent change over 1970-2021. The average annual percent change for the entire 52-year period is also traced on this chart to provide a benchmark for gauging periods of relative high--and relative low--growth against the backdrop of the long-term average.

On average, San Mateo County's population grew at an annual rate of 0.56% over 1970-2021. The county posted its highest growth in 1983 (1.78%) and posted its lowest growth in 2021 (-3.22%). In 2021, San Mateo County's population declined by -3.22%

Over the past five decades some counties have experienced extreme swings in growth, and often such swings have tended to coincide with the decades themselves. Figure 6 again shows the annual percent change in San Mateo County's population since 1970, but this time they are displayed with average growth rates for the decade of the 1970s, 1980s, 1990s, 2000s, 2010s, and 2020-2021.

During the 1970s, San Mateo County's annual population growth rate averaged 0.59%. It averaged 0.99% throughout the 1980s, 0.87% during the 1990s, 0.13% in the 2000s, 0.74% in the 2010s, -2.00% thus far this decade (2020-2021).

Figure 7 compares the decade average growth rates for San Mateo County noted in the previous graph with the corresponding decade averages for California and the nation. As the chart reveals, San Mateo County's average annual population growth fell below California's average in the 1970s (0.59% vs. 1.67%), fell below California's average in the 1980s (0.99% vs. 2.31%), recorded under California's average in the 1990s (0.87% vs. 1.38%), trailed California's average in the 2000s (0.13% vs. 0.99%), outgained California's average during the 2010s (0.74% vs. 0.68%), and lagged California's average over the 2 year period of the current decade, 2020-2021 (-2.00% vs. -0.39%).

Finally, relative to nationwide population growth trends, San Mateo County trailed the nation over the 1970s (0.59% vs. 1.10%), outpaced the nation during the 1980s (0.99% vs. 0.95%), fell under the nation during the 1990s (0.87% vs. 1.23%), recorded underneath the nation over the 2000s (0.13% vs. 0.95%), led the nation during the 2010s (0.74% vs. 0.74%), and fell under the nation over 2020-2021 (-2.00% vs. 0.25%).