The Salesforce marketing cloud connector, which can be viewed as an Email platform, consists of six report types/breakdowns:
Send
The Send report type is attributed to the send date and consists of a wide range of properties which is brought in through the Sent object from the API. Documentation can be found here. It contains overall information about email sends; for example totals and unique values.
Email performance
There are five different Email performance breakdowns to choose from; Bounces, Clicks, Not Sent, Opens and Sent. Please note that these breakdowns will not be able to fetch all data if they exceed 3 million rows of a certain event per day.
Furthermore, they can easily be merged into one dataset using the Funnel Data Explorer. These report types count events and attributes them to the even date; so whenever something happens it is attributed to that date.
All of the Email performance report types will only count events belonging to email sends that are at most 6 months old. So for example, if someone opens an email that was sent out more than 6 months ago, the corresponding open event will not be counted/inluded in the data.
Dimensions
Email Name - Specifies the name of an email message associated with a send.
Send ID - Read-only identifier for an object. Some objects use the ObjectID property as the Marketing Cloud unique ID
Metrics
Bounces - The total amount of BounceEvent objects.
Clicks - The total amount of ClickEvent objects.
Not Sent - The total amount of NotSentEvent objects.
Opens -The total amount of OpenEvent objects.
Sent - The total amount of SentEvent objects.
Limitations
Data younger than 2 days will be refreshed every 22 hours. If a backfill is needed then a recommendation is to look at which plan you’re on in order to see how many calls are allowed, since a backfill might eat up your quota. See documentation regarding the limits of the different plans here.