I think this packaged workbook contains what you are looking for. Here's how I made it.
1. Create Start Date and End Date parameters based on the date field. Right click both of them and click Show Parameter Control.
2. Create a Date Range calculated field with the following syntax:
AND [Date]>=[Start Date]
3. Drag Date Range to the Filters card and select True.
4. Create a Days to Exclude calculated field with the following syntax:
5. Right click Days to Exclude and select Show Filter.
6. Create a Number of Days calculated field with the following syntax:
7. Drag Number of Days to Text.
Let me know if this works for you.
Count Days.twbx 19.8 KB