Optmyzr’s 3-Year BFCM Study: Key Seasonality Adjustment Insights
▼ Summary
– Smart Bidding automatically increases bids during Black Friday/Cyber Monday without seasonality adjustments, as it detects rising conversion rates naturally.
– Seasonality adjustments cause CPCs to inflate roughly twice as much compared to accounts without adjustments, leading to higher costs.
– Advertisers using seasonality adjustments experienced significant ROAS declines, while those without maintained or improved ROAS.
– Seasonality adjustments can drive higher revenue but sacrifice efficiency, making them suitable only for volume-focused goals during BFCM.
– These adjustments are best reserved for unpredictable events like flash sales, not widely anticipated holidays already modeled by Google.
As the holiday shopping season approaches, many digital marketers face the annual dilemma of whether to implement seasonality adjustments for Black Friday and Cyber Monday campaigns. A comprehensive three-year study by Optmyzr reveals surprising findings that challenge conventional wisdom about these bidding strategies. Rather than enhancing performance, the data indicates that manual adjustments often undermine campaign efficiency during these predictable retail events.
The research analyzed performance across three consecutive BFCM periods from 2022 through 2024, examining up to 6,000 advertisers annually. Participants were divided into two groups: those who applied seasonality bid adjustments and those who relied solely on Google’s Smart Bidding system. The results consistently demonstrated that automated bidding algorithms already account for seasonal fluctuations without requiring manual intervention.
Smart Bidding systems naturally respond to conversion rate increases during peak shopping periods. Accounts without seasonality adjustments still saw significant conversion rate improvements: 17.5% in 2022, 11.9% in 2023, and 7.5% in 2024. The algorithm successfully detected rising consumer intent and adjusted bids accordingly, proving that artificial prompts are often unnecessary.
The study uncovered a critical issue with manual adjustments: they frequently cause excessive cost-per-click inflation. When advertisers applied seasonality adjustments, CPC increases were substantially higher compared to accounts relying solely on Smart Bidding. In 2022, CPC rose 36.7% with adjustments versus 17% without them. Similar patterns emerged in subsequent years, with adjustments consistently doubling the natural CPC inflation that occurs during peak seasons.
![Image: Graph showing CPC comparison between adjusted and non-adjusted campaigns]
Perhaps most importantly, return on ad spending suffered significantly when using seasonality adjustments. The data shows clear ROAS declines for advertisers who implemented these manual changes. In 2022, ROAS dropped 17% with adjustments compared to just 2% without them. The trend continued through 2024, where adjusted accounts experienced a 15.7% ROAS decrease while non-adjusted accounts actually saw a 5.7% improvement.
The fundamental problem lies in the precision of predictions. When advertisers specify an expected conversion rate increase through seasonality adjustments, Smart Bidding treats this as an exact forecast rather than an estimate. If the actual conversion lift falls short of predictions, the system continues bidding as if the higher rate will materialize, leading to overbidding and wasted spend.
![Image: Comparison chart showing ROAS performance across three BFCM seasons]
Despite the efficiency concerns, the research did note that seasonality adjustments can drive higher revenue volume. Accounts using adjustments generated 50.5% more revenue in 2022 and 52.8% more in 2023 compared to their non-adjusted counterparts. This creates a clear trade-off between revenue growth and profitability that advertisers must carefully consider based on their specific business objectives.
The study clarifies that seasonality adjustments remain valuable in specific circumstances. They work best for unique events where advertisers possess superior knowledge compared to platform algorithms, such as flash sales, first-time promotions, or niche events with limited historical data. However, for widely anticipated shopping holidays like BFCM, Valentine’s Day, or Christmas periods, Google’s systems already incorporate extensive historical data into their bidding models.
For PPC managers preparing for the upcoming holiday season, the research suggests several practical applications. First, consider defaulting to no seasonality adjustments for BFCM campaigns, allowing Smart Bidding to manage conversion spikes naturally. If business priorities demand maximum revenue volume despite efficiency concerns, clearly communicate the expected trade-offs to stakeholders using the study’s specific data points.
Rather than focusing on predictive adjustments, marketers should concentrate their efforts on implementing practical campaign safeguards. This includes careful budget pacing, automated monitoring systems, appropriate bid caps, audience segmentation reviews, and ensuring creative assets and offers are fully optimized for peak performance periods.
Optmyzr’s extensive research provides valuable evidence that context determines the effectiveness of seasonality adjustments. For predictable, high-volume retail events, trusting Google’s bidding algorithms typically yields better results than attempting to outsmart them with manual predictions. This data-driven approach empowers marketers to make more informed decisions and confidently navigate the complexities of holiday campaign management.
(Source: Search Engine Journal)
