Complex Working-Day Calculation

InternDD 

Here is a possible example of how this approach could be implemented in Excel:

1. Let’s say your table of data is in the range A2:C8, with column A representing the days of the week, column B representing the number of hours worked on each day, and column C representing whether or not work was performed on that day (1 for yes, 0 for no).
2. In a separate cell, you could use the MATCH function to find the first day that work was performed. For example, you could enter the formula =MATCH(1,C2:C8,0) to find the first row in column C that contains a 1 (i.e., the first day that work was performed).
3. In another cell, you could use the MATCH function again to find the last day that work was performed. This time, you would need to use a slightly more complex formula to search for the last non-zero value in column C. One way to do this is to use the formula =MAX(INDEX((C2:C8<>0)*(ROW(C2:C8)-ROW(C2)+1),)). This formula will return the row number of the last non-zero value in column C (i.e., the last day that work was performed).
4. Once you have the row numbers of the first and last days that work was performed, you can use the COUNTIF function to count the number of non-working days between those two dates. For example, if the first day worked was in row 2 and the last day worked was in row 6, you could use the formula =COUNTIF(C3:C5,0) to count the number of non-working days between those two dates.

I hope this helps!