If you send email campaigns to the same list again and again, what will happen? Will the subscribers get tired of your emails and no longer open them? Let’s see some real data.
Here we analyzed 16 campaigns sent to the exact same list (about 5,000 researchers in life sciences back in 2014-2015. The content of the email was identical for all campaigns (except for the second to last campaign). The frequency is one campaign every two weeks (except one was skipping in mid February, 2015).
Unsubscribes and bounces
First, let’s look at the unsubscribes and bounces. After 16 campaigns, the remaining number of subscribers is 76% of the original count. This means on average, we lost 1.5% of subscribers each time we sent a campaign.
Opens and clicks
Based on the chart below, we do see a decreasing open rate for the first 5 campaigns. But interestingly the open rate jumped in the middle and then dropped again. Eventually it stabilized at ~10%.
As to the click rate, it fluctuated and even increased in April-May, 2015, then it dropped and stabilized at ~0.4%. The click rate is more sensitive to random event due to its exceedingly small value.
- We lose ~1.5% subscribers every time we send a campaign
- Open rate in general decreases and stabilizes
- Click rate fluctuates