Email Marketing Metrics: 12 Key Performance Indicators You Should Be Monitoring
As you view your email campaigns, there are a number of metrics that you need to focus on to improve your overall email marketing performance. Email behaviors and technologies have evolved over time – so be sure to update the means by which you monitor your email performance.
Note: Sometimes you’ll see that I utilize Email Address and other places, Email in the formulas below. The reason for this is that some households actually share an email address. Example: I might have 2 mobile phone accounts with the same company that come to the same email address. This means that I would send two emails to a specific email address (as requested by the subscriber); however, if that subscriber takes an action such as unsubscribes… I might track that at an email address level. Hope that makes sense!
- Spam Complaints – large mailbox providers like Google get so many emails from email service providers that they typically maintain a reputation for each sender by IP address. If you get more than a handful of subscribers reporting your email as spam, all of your email may simply get routed to the junk folder and you don’t even realize it. A few ways to keep spam complaints low are to offer double-opt-in on subscriptions, never import purchased lists, and offer your subscribers the ability to modify their subscription or unsubscribe without a lot of effort.
- Bounce Rates – bounce rates are another key indicator to mailbox providers on the engagement level of your email. High bounce rates may be an indicator to them that you’re adding email addresses that may have been purchased. Email addresses churn quite a bit, especially in the business world as people leave jobs. If you start to see your hard bounce rates rise, you may want to utilize some list cleansing services on a regular basis to reduce known invalid email address.
- Unsubscribe Rates – The quality of your email’s design and content is critical in keeping your subscribers engaged and driving them to the activity you’re seeking. Unsubscribes may be an indicator that you’re also sending too often and bugging your subscribers. Test your designs across platforms, monitor the open and click-through rates on your emails, and offer your subscribers different frequency options so you can keep them.
Unsubscribe Rate = ((Number of Email Addresses who unsubscribed) /(Number of Email Addresses Sent – Number of Email Addresses Bounced)) * 100%- Acquisition Rate – it’s said that up to 30% of a list can change email addresses in the course of a year! That means in order for your list to continue growing, you have to maintain and promote your list as well as retain the rest of your subscribers to remain healthy. How many subscribers are lost per week and how many new subscribers are you acquiring? You may need to better promote your opt-in forms, offers, and calls-to-action to entice site visitors to subscribe.
List retention can also be measured once you know how many subscribers are acquired versus lost in a given period. This is known as your subscriber churn rate and can provide you with the metrics you need to understand your list growth rate.
- Inbox Placement – avoiding SPAM folders and Junk filters must be monitored if you’ve got a significant number of subscribers (100k+). Your sender’s reputation, the verbiage used in your subject lines and the message body… all of these are critical metrics to monitor that aren’t typically offered by your email marketing provider. Email service providers monitor deliverability, not inbox placement. In other words, your emails may be delivered… but directly to the junk filter. You need a platform like 250ok to monitor your inbox placement.
Deliverability Rate = ((Number of Email Addresses Sent – Number of Email Addresses Bounced) / (Number of Email Addresses Sent)) * 100%- Sender Reputation – Along with inbox placement is the reputation of your sender. Are they on any blacklists? Are their records set up properly for Internet Service Providers (ISPs) to communicate and verify that they’re authorized to send your email? These are problems that often require a deliverability consultant to help you set up and manage your servers or verify the third-party service you’re sending from. If you’re utilizing a third party, they could have awful reputations that get your emails directly in the junk folder or even blocked altogether. Some people utilize SenderScore for this, but the ISPs don’t monitor your SenderScore… each ISP has its own means of monitoring your reputation.
- Open Rate – Opens are monitored by having a tracking pixel included in each email sent. Since many email clients block images, keep in mind that your true open rate will always be much higher than the actual open rate you’re seeing in your email analytics. Open rate trends are important to watch because they point to how well you’re writing subject lines and how valuable your content is to the subscriber.
Open Rate = ((Number of Emails Opened) /(Number of Emails Sent – Number of Emails Bounced)) * 100%- Click-Through Rate (CTR) – What do you want people to do with your emails? Driving visits back to your site is (hopefully) a primary strategy of your email marketing campaigns. Ensuring you have strong calls-to-action in your emails and you’re promoting those links effectively should be incorporated into design and content optimization strategies.
Click-Through Rate = ((Number of unique Emails clicked) /(Number of Emails Sent – Number of Emails Bounced)) * 100%- Click to Open Rate – (CTO or CTOR) Of the people that opened your email, what was the click-through rate? It’s calculated by taking the number of unique subscribers who clicked on a campaign and dividing it by the unique number of subscribers who opened the email. This is an important metric because it quantifies the engagement with each campaign.
- Conversion Rate – So you got them to click, did they actually convert? Conversion tracking is a feature of many email service providers that’s not taken advantage of as it should be. It typically requires a code snippet on your confirmation page for a registration, a download, or a purchase. The conversion tracking passes the information back to the email analytics that you’ve actually completed doing the call-to-action that was promoted within the email.
Conversion Rate = ((Number of Unique Emails resulting in a Conversion) /(Number of Emails Sent – Number of Emails Bounced)) * 100%Once you understand the value of your conversions over time, you can better predict your average revenue per email sent and average value of each subscriber. Understanding these key metrics can help you to justify additional acquisition efforts or discount offers to drive list growth.
Return on Marketing Investment = (Revenue obtained from Email Campaign / ((Cost per Email * Total Emails Sent) + Human Resources + Incentive Cost))) * 100%Subscriber Value = (Annual Email Revenue – Annual Email Marketing Costs) / (Total Number of Email Addresses * Annual Retention Rate)- Mobile Open Rate – This is so huge nowadays… in B2B a majority of your emails are opened on a mobile device. This means that you have to pay special attention to how your subject lines are constructed and ensure that you’re utilizing responsive email designs to be viewed properly and improve overall open and click-through rates.
- Average Order Value – (AOV) Ultimately, tracking an email address from a subscription, through nurturing, through conversion is critical as you’re measuring the performance of your email campaigns. While conversion rates may remain somewhat consistent, the amount of money subscribers actually spent may vary quite a bit.
The vast majority of companies are concerned with the total number of email subscribers they have. We recently had a client that hired an agency to help them grow their email list and they were incentivized on list growth. When we analyzed the list, though, we found that the vast majority of acquired subscribers had little or no impact on the value of their email program. In fact, we believe the lack of opens and click-throughs was damaging their email reputation overall.
We cleansed their list and purged approximately 80% of their subscribers that hadn’t opened or clicked in the last 90 days. We monitored their inbox placement over time and it skyrocketed… and subsequent registrations and call-to-action clicks increased as well. (Not the rate, the actual counts). Not to mention that we saved them quite a bit of money on their email platform – which charged by the number of active subscribers!
Email Marketing Analytics
There’s a great book out there from Himanshu Sharma on everything you need to understand about email marketing analytics.
Master the Essentials of Email Marketing Analytics: The Journey from Inbox Placement To Conversion
This book focuses solely on the analytics that power your email marketing optimization program as well as the techniques to improve your email marketing performance.
