That was one of the questions my company wanted to answer in its annual study of email marketing benchmarks. We found some interesting results when we compared email activity on retail and ecommerce messages sent between Black Friday and New Year's Eve:
-- Open and click-through rates were lower in this period compared with emails sent the rest of the year. The mean (average) unique open rate during the holiday period was 17.6%, compared with 20.9% for the rest of the year, while the mean unique click rate was 2.8% (3.6% rest-of-year). The click-to-open rate, however, was comparable (14% holiday, 14.8% rest-of-year).
-- Hard bounces, unsubscribes and spam complaints also were lower compared with rest-of-year mailings. Hard bounces were 2.4 times higher in the non-holiday mailing season. Results were closer for unsubscribes (0.10% holiday/0.12% non-holiday) and spam complaints (0.010% holiday/0.014% non-holiday).
Now, do you expect me to conclude that increasing frequency will kill your open and click rates but reduce list churn? Not so fast.
The "Frequency Math Effect"
Sending more frequently to your database can affect email performance and metrics. Another factor, one that isn't as easily identified, is the Frequency Math Effect. This comes into play when you compare changes on rates (percentages) instead of total or cumulative numbers.
When you increase your email cadence, you increase your total email touches. But, you're also giving your recipients more opportunities to ignore or to unsubscribe from your messages.
Suppose you move from emailing four times a week to daily, or from once a day to twice daily. The total number of emails you send will go up, but you'll normally see a decline in activity rates because your recipients don't usually change their open or click habits at the same pace.
This holds true for list-churn metrics, too. When you increase frequency, your recipients have more emails to act on, whether it means unsubscribing or clicking the "report spam" button. If subscribers aren't opening emails at the same rate they do when you send less frequently, these rates also will go down.
This doesn't mean you should run into your boss's office and brag about how you reduced list churn when you increased frequency, because you would be wrong. You might just be spreading more recipient actions over a larger number of emails. That's the frequency math effect.
Look at the Total, Not Just the Rate
To get a more telling view of email frequency and its effects on performance, add up all email actions (opens, clicks, conversions and resulting revenue, unsubscribes, spam complaints and hard bounces) to get a total number for the entire time period.
Compare this number to a period when you have lower frequency, and you will see whether increasing frequency resulted in more positive email activity, including -- I hope -- higher revenue or conversions. But you will also find that you incurred more list churn through unsubscribes, hard bounces and spam complaints.
The numbers in the chart below show both rates and actual numbers for opens, clicks and unsubscribes generated on higher frequency in the holiday period:
Your Big Question
Are you meeting your business goals (acquisition, conversions, revenue, upgrades, order value or whatever you need to fulfill the plan)? Was the increased revenue worth the tradeoff from higher list churn?
That's a call only you can make.
Until next time, take it up a notch.