Last year we improved our metrics report to be automatically updated monthly. We also modified the way we calculate some of the stats from an aggregate model to a per send model. This is to remove any skew from significantly large senders. For example we have 10 customers, 9 of them send 10 emails with a 50% open rate, 1 of them sends 1 million with 1% open rate:

Aggregate would be:

number sent: 1000090 emails

number opened 10045

open rate: 1.01% (approx)

Per send rate would be:

overall open rate: 50 x 9, 1

average open rate: 45.1%

We also no longer breakdown the data by list size. Looking at data by list size becomes less important if you have an engaged opt in list.