Create a Saved Search that Displays the Total Number of Days a Case has been Open

1. Navigate to Lists > Search > Saved Searches > New.

2. Click on the Case link.

3. Under Criteria tab > Standard subtab, set the following filter:
    - Stage is any of Escalated, Open

4. Under Results tab > Columns subtab, set the following:
    - Field: Formula (Numeric)
    - Function: Round
    - Formula: {today}-{createddate}

5. Click Preview.