---
schema_version: "1"
id: 9f8921bdf88bd02f6a12efd0ab87893b2d4ac35af85619712fc6bece6cb5f681
title: Field Mapping for Reach Data Streams
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/mktg/264-0-0/dato_data_reach_field_mapping_data_streams.md
canonical_url: https://help.salesforce.com/s/articleView?id=mktg.dato_data_reach_field_mapping_data_streams.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: 648a7a8bf9301cb7354c42b960de69f59a1d47b867977687ed935dc82ab1648d
description: It’s important to map the day and reach fields correctly in a reach data stream. The mapping can vary depending on the granularity that you’re setting up. Only map the required fields.
products:
  - Marketing
  - Marketing Cloud Intelligence
release: "264"
---
# Field Mapping for Reach Data Streams

It’s important to map the day and reach fields correctly in a reach data stream. The mapping can vary depending on the granularity that you’re setting up. Only map the required fields.

Mapping the **Day** field for reach data:

- For a 31-day granularity, the formula for the day field is:
    
    ```
    Day = csv['fb.date_stop']
    ```
- For a 7-day granularity, the formula for the day field is:
    
    ```
    Day = var date = csv['fb.date_stop'];
    var dayofweek = FORMATDATE(date, 'u');
    if(dayofweek != 1)
    {diff = dayofweek-1;
    return date = DATEADD('d',-diff,date);}
    else {return date;}
    ```

Mapping the **Reach** measurement for reach data:

- ```
    Reach = csv['fb.reach']
    ```