How to Calculate the Potential Impact of Increased Email Frequency

If you've already accelerated your email program's sending frequency, use this set of equations to determine whether the increase helps or harms your bottom line:

1. Determine the "before" and "after" frequency (how many individual messages or campaigns you send per month to your entire list, excluding any targeted or transactional messages, and the number you increase to or plan to send on the new schedule).
   
   
2. Calculate the following costs and figures for a month of messages:
   • Lost subscribers (average, using results from a month of messages): Hard bounces + addresses associated with spam complaints + unsubscribes = lost subscribers
     
     
   • Message distribution costs: (CPM x number of subscribers x number of messages) + accreditation fees + deliverability monitoring + labor, agency, and/or ESP fees = message distribution costs
     
     
   • Creative costs: Labor and/or agency fees + image purchase = creative costs
     
     
   • Reacquisition costs: Your cost to acquire a prospective customer's email address
     
     
   • Potential lost revenue: Use average annual revenue per subscriber/customer. If you don't know this figure, divide your email program's annualized revenues by the average number of subscribers for the year. Because the people who unsubscribe or file a spam complaint were likely your least valuable customers, you should probably reduce the annual revenue lost by some factor, such as 50 percent.
   
   
3. Plug those numbers into this equation: Annual distribution costs + annual creative costs + (annual lost subscribers x reacquisition costs) + (annual lost subscribers x potential lost revenue) = annual lost/gained revenues