Where Trends data comes from
Google Trends analyzes a percentage of Google web searches to figure out how many searches were done over a certain period of time.
For example, if you search for
tea in Scotland in March of 2007, Trends analyzes a percentage of all searches for tea within the same time and location parameters.
Data that is excluded
- Searches made by very few people: Trends only analyzes data for popular terms, so search terms with low volume appear as 0.
- Duplicate searches: Trends eliminates repeated searches from the same person over a short period of time.
- Special characters: Trends filters out queries with apostrophes and other special characters.