Google appears to have added a forecast function to Insights for Search, allowing predictions of search volumes up to 12 months ahead. See the query here for “bonds”.
There is already some guidance in the Google help pages as to the background calculations involved:
Insights for Search examines the past values for the terms you’ve entered. Based on those values, it extrapolates the future values, creating a forecast of search trends for those terms.
Obviously this is a useful additional function, however as the prediction model doesn’t take into account the context of the search term, or account for any business cycles that may be driving a specific market, these numbers may prove to be misleading at best.
There could be some interesting applications of this, certainly in terms of understanding Google’s view on the direction of either particular brands or keyword markets. Beyond that it will be interesting to track over the next few months the accuracy of any predictions made.