If you are a company with a sizeable email marketing budget and list you will be interested in increasing sales or increasing leads. But what should you key performance indicators be?
Some choices for a ecommerce-driven business are:

Sales (total sales, sales by campaign/type/segment/cell, per e-mail delivered)
Profit/margin per e-mail sent and campaign level
List growth/churn (size of database, growth month over month, churn rate month/aggregate)

Some companies are more about lead generation than pure sales. They want to get a lead into the hands of a partner or call centre or salesperson–so they are about efficiencies, rather than sales and/or profit margin. There choice could be:

1. Cost per lead
2. Funnel movement (how leads migrate through the funnel stages)
3. Total reach (how much of the prospect database can be reached at any given time). This includes churn metrics as well.

Notice that the primary KPIs for the two instances above are not about click-through rate or open rate.

When the real focus of the program is purely branding, the metrics seem simpler, but with a deeper definition:

1. Response rate (both open and click). Brand marketers are increasingly looking at the total reach of their base and less at campaign-over-campaign results. They want to count how many eyeballs were exposed to the brand each month, the resulting interactions and incremental Web exposures.
2. Site visits and site journeys. Site traffic statistics driven from e-mail are becoming increasingly valuable to see what content and interests are driven from each campaign/program and business division. Depth of site exploration… List growth. See how email traffic performs against searches made, types of products bought so you can define your personas against email marketing.

All brands place increased value on the size and relative growth of the database since it represents a potential share of market and voice. It is essentially the lifeline to reach a mass of customers in an efficient manner. This, combined with qualitative feedback, is quite useful in measuring brand attitude, awareness and level of involvement with the brand.
So also for example in this context thinking about how to encourage higher subscription rates to an email newsletter via personalised call to actions based on site activity or cookie id to move more people from your bottom left to top right (great customers).
Here are some standard KPIs but obviously every company’s KPIs will be different and will need to evolve over time as well.

E-mail KPIs:

E-mail sent/delivered
Campaign over campaign impressions/opens (total/unique/% rate)
Campaign over campaign clicks (aggregate/unique /% rate)
Click to open (% who open the message and click through)
Churn rate (% unsubscribe/opt out/undeliverable)
Send to a friend (viral rate)
ISP domain response (open/clicks)

Commerce-Driven Program KPIs:

Total sales (campaign, month, quarter, segment)
Profit/margin per e-mail sent / source
Sales per e-mail sent
Cost per e-mail sent
Average Order Value (AOV)
Number of orders
Conversion rate (to open/click through)
Number of site visits (page rank)

Demand Generation

Number of leads (by product/client type)
Number of downloads
Site visits
Page Rank
Cost per lead
Conversion rate
Membership/subscription/database growth

Web Focused

Cost per visitor
Number of leads by entry page
Heavy user share
Average page views
Stacking effect
Length of site visit by source

What do you think? Have I missed some that you think glaringly obvious…
Thanks so much for reading