Statistical information often serves as persuasive evidence,
because it provides a good way of measuring trends and
identifying factors that are related to each other without
relying on individual cases. However, you should always make
sure that you understand how the statistics that you are using
were gathered. Pay attention to the sample size and how members
of that sample were selected. If you need a quick fact, there
are several books in our reference section on Level 3 you may
want to consult, including The World Almanac and Book of Facts.
Longer and more detailed requests for statistical information,
such as the census, may require you to search statistical
websites and databases online. Here is a list of useful sources
of statistical information. Several of them are provided by the
United States government, which maintains some good sources for
statistical data on the Web. - American FactFinder Population
data based on the US Census. Provides access to the full range
of official statistical information