Compare rows based on date - see description

I have rows of data based on dates and employee details.

For eg, I have date column, employee ID and Prokect ID. The data is from january 1st to january 22nd.

I want to compare each dates data and see if there is any change in the employees ID for the next date.

If i have 200 employees on january 1 and 203 employees on january 2,  I need to show the difference as 3 in the new column.

How can i do the row comparison and do this calculation?

(1) Answer