Need to find the date difference between two dates in Compensation Worksheet

Summary

Need to find the date difference between two dates in Compensation Worksheet

Content

In compensation worksheet we need to derive Days between two dates dynamically. We need to get the number of days between "Next Review date" from employee's salary and "Effective revision date" which is a user entered date. This effective revision date will be different for each employee and worksheet manager would be populating the date. 

The proration starts by deriving the number days between these 2 dates which is "365 - (Next Review date - Effective Revision Date)". All other calculation starts using this "Prorated Days for Increment" value.