Employee New Hire

New Hires =
var minDate = MIN('Date'[Date])
var maxDate = MAX('Date'[Date])
return CALCULATE( COUNTROWS( 'Staff' ), 
    REMOVEFILTERS( 'Date'[Date])
    'Staff'[HireDate] <= maxDate && 'Staff'[Hire Date] >= minDate
)

Should work at any level of the date hierarchy

Hi Siddiq8686 ,
First you need to build a new "inactive" relationship like this

Your measures would be

New Hires = 
CALCULATE ( 
    COUNTROWS ( VALUES ( Payroll_Merge_File[Employee #] ) ),
    USERELATIONSHIP ( Calendar_Table[Date],Payroll_Merge_File[Hire Date] )
)

Total Staff = 
VAR LastDateInFilter = 
    CALCULATE ( 
        MAX (Payroll_Merge_File[Hire Date] ),
        USERELATIONSHIP ( Calendar_Table[Date],Payroll_Merge_File[Hire Date] )
    )
VAR Result =
    CALCULATE ( 
        COUNTROWS ( VALUES ( Payroll_Merge_File[Employee #] ) ),
        USERELATIONSHIP ( Calendar_Table[Date],Payroll_Merge_File[Hire Date] ),
        Calendar_Table[Date] <= LastDateInFilter
    )
RETURN
    Result

Your report shall look like this

Please note that currently your Calendar Table starts from 2019 while hiring data starts from 1976. Therefore you need to update you Calendat Table to include all missing dates.
Hope this answers your query. Have a great day!