Statistical books are often compilations of statistics gathered by governmental agencies or private researchers. Statistics are presented in tables. Just like a bibliography, the source can be used to pursue more in-depth analysis of the information presented. General books and articles on a topic may provides statistics. An article on AIDS in Newsweek may very well contain current infection rates.
Statistics are labor-intensive to gather and present.
Often, the most currents statistics will be several yars behind the current calendar year. The number of births, especially since they need to be registered, is an easy statistic to locate. The second thing to ask when thinking about statistics is who might possibly keep track of the statistics you are looking for. Probably the U.S. Department of Transportation. Probably the Minnesota Department of Health.