Due to the metric requirements and date partitioning used in the Funnel platform three Funnel fields are added to each Salesforce dataset for integration purposes. 

Number of {"Salesforce Object"}:
The "number of" metric is added in order to count the number of objects in a dataset (for leads this would be called: Number of Leads). This field will be set to the value of 1 for each row.

Date:
https://help.funnel.io/en/articles/3738055-how-is-funnel-s-date-dimension-populated-for-salesforce-data

Currency:
Currency is selected by the user in the connector setup, this field should equal the currency used by organization.