Information is power. And when it comes to measuring the success of e-mail marketing campaigns, there is no shortage of information available for reporting and analysis.

The challenge is that we sometimes become more interested in the numbers associated with our campaigns than with the only number that really matters – orders.
One of the great characteristics of e-mail marketing campaigns – any direct response campaign for that matter – is that results are immediate and measurable. For example, here are just a few of the metrics associated with e-mail marketing campaigns and their implications for on-going campaign success:
Delivery rate: Life would be easier if every e-mail sent was delivered. But just like postal mail, not every message can be delivered.

For e-mail marketing, a high delivery rate is the direct result of database hygiene and/or the credibility of the sender’s IP address. A high delivery-failure rate suggests poor database hygiene and/or issues with the sender’s IP address.

The implications for on-going campaign success are significant. E-marketers that continue to include failed e-mails in their campaigns may not realise that E-mail Service Providers (ESPs) keep track and score their sending IP based on the percentage of bad (non-deliverable) e-mails received. Over time, sending to known non-deliverable e-mail addresses will result in ESPs blocking your IP address.  
Tracked HTML open rate: While the average tracked HTML open rate is 15% across all types of e-mail campaigns, it is not unusual in the newspaper industry to achieve open rates with current subscribers that exceed 45%.

First, realise that tracked HTML open rates are based on e-mail recipients downloading a graphic in your e-mail message. Many e-mail clients default to blocking the downloading of graphics under the guise of protecting privacy.

For this reason, to get a true picture of “all opens,” your campaigns should track those clicking on links in your e-mail but not downloading graphics.

Once again, the implications for campaign success are significant. Your e-mail messages should be designed in such a way that recipients can read your message without downloading graphics. How many times have you previewed an e-mail only to see boxes with red X’s?

Subject line (hint: include your publication name) and e-mail layout and design are critical for not only getting delivered but also getting read; without both, there are no orders to count.

ESPs and spam filters measure the percentage of images to text in the e-mails you send. E-mails that are entirely made up of graphics receive higher spam scores and are more likely to be placed in spam folders or quarantined.

Yes, it is easier to just e-mail that .jpg image, but realise fewer contacts will receive and read your message and, as a result, your conversion rate will suffer dramatically.
Unsubscribe rate: Even when employing permission-based marketing practices, contacts will unsubscribe from receiving future e-mail communications. While the average unsubscribe rate for sales campaigns is less than 1%, high unsubscribe rates suggest there are issues with your opt-in process and/or your messages/offers are poorly constructed or targeted.

If your database consists of nothing more than e-mail addresses (i.e. no subscription information), you are using a one-to-one channel (e-mail) to blast your message to a mass audience.

While it is easy to justify why everyone would be interested in what you have to offer, the reality is that misdirected campaigns have a negative impact on future e-mail campaign delivery and results.

ESPs track the percentage of their customers reporting your e-mail message as spam and recipients can block future messages from your IP address and/or from e-mail addresses with a couple of clicks. Loading up a list of e-mails and blasting messages guarantees your long-term e-mail marketing success will be limited, at best.

The solution is to know your audience and tailor your message based on what you know about your target audience.
Click-through rate: While click-through rate is a measure of e-mail message effectiveness, it does not guarantee campaign success.

First, be sure your e-mail campaign software can discern distinct click-through tracking from total click-throughs. Total click-through tracking counts multiple click-throughs by individual contacts – a contact clicks the same link five times – while distinct click-through tracking only counts one click-through per contact.

It is not unusual for contacts to click on an e-mail link more than one time, and that is why the true measure of success is how many of those clicking through actually complete your online form.
Click-through-to-form-completion rate: E-mail recipients click on links in e-mails because they are either curious or are sincerely interested in what you have to offer. Measuring the percentage of contacts that click on a link and complete your online order form can reveal issues related to your e-mail message or the online form itself. Not every contact that clicks through to your online order form will complete the form. 

A click-through-to-form-completion rate lower than 30% suggests your e-mail message might not have clearly communicated your offer or your form does not reflect the offer as it was communicated in your message. For this reason, it is important to clearly communicate your offer (price, term, disclaimers) in your e-mail message and carry that offer through to your online form.

Ideally, your online form should look like your e-mail message to build confidence with respondents and increase order conversion.
While other e-mail campaign metrics provide an opportunity to learn and improve your efforts over time, at the end of the day, the true measure of e-mail campaign success are completed orders.