Historical search data, describing the volume of searches by topic and region, have recently become freely available. This provides a potentially valuable source of data useful for business intelligence about conditions external to the organization where data is sometimes sparse. As an experiment for a business application, Google searches on the keyword “foreclosure” were correlated with actual U.S. home foreclosures over the past 4 years. The resulting regression analysis shows a very good correlation, indicating that searches on “foreclosure” provide a very accurate estimate of trends in actual U.S. home foreclosures and may provide an early warning system. In a related non-business experiment, Google has recently reported success in showing that searches on the term “flu” track closely with worldwide outbreaks of flu.
G. Kent Webb. "Internet Search Statistics as a Source of Business Intelligence: Searches on Foreclosure as an Estimate of Actual Home Foreclosures" Issues in Information Systems (2009): 82-87.