Google will be making more data available in the Keyword Planner Tool, so you can make informed decisions about your search campaigns. The new metrics in the Google Keyword Planner Tool will include year-over-year change, three-month change and trend type.
The year over year change compares the monthly search volume of the latest month with the same month the previous year.
Three month change
The three month change shows a three month change in search trends by comparing the latest month’s data, with the data from two months prior. For example, if the latest month is July, the July data would be compared to May to show change in search volume over three months.
Three month trending type
This shows you if the trend is going up or down or remaining flat for the keyword.