Once the campaign is sent and engaged with, it opens you up to new avenues of measurement. People may engage your content by clicking / taking forth a CTA. Some may also disengage you by unsubscribing from your list, reporting spam etc. People may share your content by forwarding or sharing it on social media. This in turn results in your content popularity and list growth, and ultimately translated to Return on Investment.

2.  Once the campaign is sent and engaged with, it opens you up to
new avenues of measurement.
 People may engage your content by clicking / taking forth a
CTA
 Some may also disengage you by unsubscribing from your list,
reporting spam etc.
 People may share your content by forwarding or sharing it on
social media.
 This in turn results in your content popularity and list growth,
and ultimately translated to Return on Investment.

3.  Denotes percentage rate of conversions which
specifically lead to CTA of a campaign like download
an e-book, fill an e-survey firm, complete a purchase,
schedule a demo etc.
 It is a success measure of you email campaign.
 It has to be tracked by an internal tracking
mechanism, as the ESPs do not generally receive the
sensitive CTA information.

4.  Gives an idea about the percentage of users who has
unsubscribed to the emails delivered.
 A low unsubscribe rate (<0.2%) will not require your
concerns, but if rates soar higher than 2%, caution has
to be made.
 It is always a good prospective to ask your users the
reason for unsubscription through a short and concise
feedback form.

5.  This gives the ratio of the number of people who has
marked your campaign as spam to the number of emails
delivered and is expressed in percentages.
 A high spam rate signifies a lot of things – you might be
sending without the user permission, or delivering
irrelevant content, or delivering mails too frequently, or
sending out annoying content.
 A good content score and sender reputation built over
time can probably bring down your spam rates.

6.  It gives you the increase in the number of your list size
after deducing the number of people who have opted out
of your list.
 It gives the increase in attention gathered by your email
campaign.
 A proper list growth strategy including opting in your users
has to be maintained if you are to achieve a clean list.
 You also have to make sure that you also gather user
preferences of your growing list to achieve better
targeting.

7.  ROI refers to the revenue generated by your
campaigns.
 It is expressed in ratio such that, if X refers to the
amount generated from your campaign and Y denotes
the amount spent on it, then X/Y gives your ROI.
 ROI tracking will help you generate more insights on
your fund flow and resources allocation for your entire
marketing efforts.