At a keyword level, you will have the Year-over-Year search trends expressed as a positive or negative percentage (or multiplier), comparing the search volumes from the last month to the same month of the previous year. And we also calculate the same metric at a group level.
How does this work?
SEOmonitor retrieves monthly Google Ads search volume data for each keyword. Every month, starting around the 15th, Google Ads starts providing the data for the previous month. Not all keywords get data on the same day, so our system runs this process continuously until all of the keywords in the campaign have data. It then compares the last available month’s search volume to the same month one year ago.
Keyword-level Year-over-Year search trends
This metric is usually displayed as a percentage, but if the trend is higher than +100%, it will be shown as a multiplier, such as "x2":
Keywords with a trend greater than +1000% – usually with negligible previous search volume – are marked as newcomers with a corresponding icon:
When there are high shifts, the keywords are considered exploding or tanking, and they are grouped in the Shifting Trendssmart group, accordingly. A clear example would be the newest iPhone model versus a previous model.
Group-level Year-over-Year search trends
Here's the formula we use to calculate the Year-over-Year search trend at a group level:
Sum[SearchVolume(previous_month)] & Sum[SearchVolume(13th month)]
In this formula, only the main keywords in the given list are considered, while close variations are excluded.
We won't always have the YoY information once you start tracking a keyword because at least 13 months of search volume data are needed to calculate the trend, and Google Ads' API only provides the last 12 months. If the keyword is already part of SEOmonitor's keyword databases, you will have this data readily available. If not, it will become available within the next 30 days.
It's not uncommon for multiple keywords have the exact same trend values (for example +18% or -33%). These only feel like patterns, and it happens because of the search volume thresholds from Google Ads. The search volumes are provided on a non-linear scale, so their trends would appear to also be on some "tiers". You can read more about this here.