6 Email Metrics You Can't Live Without

On Tuesday, I presented a Return Path-sponsored webinar hosted by the EEC called “The Email Metrics You Can’t Live Without.” If you’d like to access the presentation, you can visit SlideShare, or email me for a PDF.

With more data about email being available than ever before, a seemingly endless array of metrics to track to gauge performance, and a real-time stream of customer behavioral metrics to marry-up with data from other channels, it’s very easy to reach analysis paralysis before you even open a spreadsheet.

Our goal at Return Path is to make email marketers’ jobs easier by not only providing data, but extracting the intelligence that you need to make meaningful program decisions that deliver ROI. While we offer a suite of email solutions that provide intelligence around inbox placement, engagement and brand protection and security, it helps to have foundational metrics to get you started.

What are those foundational email marketing metrics, or the ones you can’t live without? Here’s are the six metrics I covered in Tuesday’s webinar:

  1. Inbox Placement Rate: The Inbox Placement Rate is the percentage of emails that land in the inbox, as compared to the spam or junk folder or those not delivered at all. It goes far beyond subtracting your bounces from your total messages sent  and instead, gives you an accurate picture of where you may be having deliverability issues, broken down specifically by ISP. With 23% of global opt-in email never reaching the inbox, this is a very important metric to track. As we’re fond of saying at Return Path: “No inbox, no click, no ROI.” If you’d like to learn more, access some great global deliverability stats and discover ways to improve your inbox placement rate, you can download  our latest Global Email Deliverability Benchmark Report.
  2. Complaint Rate: this is the percentage of emails delivered to the inbox that subscribers mark as spam or junk. It’s a very important metric because it represents a level of dissatisfaction with your program. For example, the subscriber may not like your message content, frequency or may not even understand why they’re receiving email from you if the permissioning and sign-up process wasn’t clear. Complaints are a primary driver of sender reputation and sender reputation accounts for 77% of email filtering decisions.
  3. Unknown User Rate: this is the percentage of email addresses on your list that do not exist or aren’t deliverable. This metric says a lot about your list hygiene practices, and ISPs don’t like seeing high unknown user rates because it means you’re working with old data or unclean data, much like a spammer would.
  4. Spam Trap Rate: This is another indicator of poor list hygiene practices and represents the amount of pristine or recycled spam traps you have on your email file. If you’re working with poor data – for example, as a result of purchasing lists from sources that haven’t been properly vetted–  or old data, such as sending to subscribers who have never responded, you’re likely to see a higher percentage of spam traps on your file. Spam traps are also very damaging to sender reputation scores. To learn more about the factors impacting sender reputation, download Return Path’s 2012 Sender Score Benchmark Report.
  5. Open by Device Rate: With the growth of mobile email and the ever increasing usage of smartphones, knowing the device your subscribers are using to access your email is becoming essential for maintaining email program ROI. Why? Our study showed that 63% of Americans and 41% of Europeans would either close or delete an email that wasn’t optimized for the mobile experience.
  6. Read Rate: This is a great metric to use in combination with the open and click data you have today and provides another perspective on your subscribers’ engagement levels with your program. The read rate is different than the open rate because it’s not based on an image pixel. The read rate is based on mailbox providers marking the message as “read” due to subscriber activity in the inbox. Return Path incorporates this data into our Inbox Insight tool from a panel of anonymized subscribers and also shows you how your read rates, and other engagement metrics, compare to your competitors.

Email intelligence has never been more important for program success, and tracking and optimizing these metrics will ensure your messages get seen, read and acted on.

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