Seasonality adjustment is a signal for the automated bidding algorithm about when to expect performance changes. It eliminates the need for manual bid adjustments by automatically optimizing the bids but a performance increase is not guaranteed.
It is likely to help with performance during the timeframe specified on the adjustment page but advertisers shouldn’t rely only on this feature for performance improvement.
Additionally, seasonal adjustments are effective under certain conditions only:
- Only applicable for campaigns with Target ROAS (return on ad spend) and Target CPA (cost per acquisition) bid strategies
- It should only be used for campaigns with stable performance with automated bidding and have already completed their learning period
For example, think about the fashion industry. Most events are in spring and summer. Therefore, fashion shows, fashion magazines, and modeling courses should you seasonality adjustments in early spring to make the most out of the upcoming demand.
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