The objective of Google Correlate i

The objective of Google Correlate is to surface the queries in
the database whose spatial or temporal pattern is most highly
correlated (R2
) with a target pattern. Google Correlate employs
a novel approximate nearest neighbor (ANN) algorithm over
millions of candidate queries in an online search tree to
produce results similar to the batch-based approach
employed by Google Flu Trends but in a fraction of a second.
For additional details, please see the Methods section below.