Annual Leave Form - Sum the workdays (value of 1) if they fall between Start Day & End Day

Hi All,

Please see attached my Annual Leave Form.

In cell M16 I want to sum the amount of work days (referencing values in column BC) that fall between the Start Date (M12 & U12) and End Date (M14 & U14) of the Annual Leave being requested.

To give you some background of the premise of column BC:
- All days of the year are split into two rows - AM and PM
- Workdays are AM & PM Monday - Friday and also Saturday AM
- If a row constitutes a workday, it is given a value of 0.5 in column BC
- If a row constitutes a non-workday (Saturday PM or Sunday AM and Sunday PM) then it is given a value of zero.
- If a row constitutes a public holiday (see list AR24:AR47) then it is also given a value of zero.

Cell M16 needs to sum the number of '0.5' workdays that are being requested in an employee's annual leave request. It will need to do this based on the days and AMs/PMs they are requesting off work, as per the Start Date (M12 & U12) and End Date (M14 & U14), probably by using some permutation of COUNTIF, INDEX & MATCH to reference the criteria in M12, U12, M14 and U14 to the values AX & BB & BC (this is the part I'm having problems with).