Why Is This Important?
Population, the environment, and quality of life are intimately linked. The degree of environmental impact caused by a society depends on its population size, per-capita consumption, and the efficiency of resource use. Since Americans have high consumption rates (Americans comprise only 4% of the world's population but use 25% of its resources), our environmental impacts per person are large.

Population growth increases human demands on land and other resources. In order to offset the environmental impacts associated with a growing population, it is necessary to use resources more efficiently and to reduce consumption per person. Long-term sustainability requires population stabilization, which results when the average number of children born per female remains about 2.10 for an extended period of time.

How Are We Doing?
Santa Clara County began this century with a human population of about 60,200. Almost a century later, our County's population has increased to just over 1.7 million people -- 28 times the size at the turn of the century. The total population of Silicon Valley is more than 2.3 million people.

The County's population has increased 31% since 1980. About three-quarters of this growth is driven by "natural increases", or the excess of births over deaths. The remaining one-quarter of the County's population growth is due to an inflow of new residents, about half of which has come in the last three years.

Data Source: California Department of Finance, Demographic Research Unit

The average number of children born per female (the fertility rate) in Santa Clara County has ranged from approximately 2.11-2.16 since 1990, which is slightly higher than 2.10 -- the rate required for long-term population stabilization (not accounting for population changes caused from migration). Although the County's fertility rate is only slightly higher than the "replacement rate" of 2.10, small increases in population growth rates translate into large numbers of additional people.