Network days function in excel

In Excel, I want to use the NETWORKDAYS function on a table in another sheet.

This is the formula I am using. Details is the table name

=NETWORKDAYS(Details[Date1],Details[Date2])

The formula is returning a #Value! error.

How can I use a table name in the NETWORKDAYS function?

Source Data: Range vs Array

According to barry houdini's accepted answer to this question , the NETWORKDAYS function accepts arrays as arguments, but not ranges. I have tested and confirmed this to be the case.

This explains why your formula is failing as you are you trying to pass in two ranges: Details[Date1] and Details[Date2]. If you first convert the two ranges to arrays, NETWORKDAYS will successfully output an array of values.

It is simple enough to convert the ranges to arrays by adding zero to each range, or multiplying or dividing the ranges by one:   +0 , *1 , or /1

New Formula

=NETWORKDAYS(Details[Date1]+0,Details[Date2]+0)

_{Formula Example}<br>
[<img src="https://i.stack.imgur.com/1GCbd.png" width="500" />](https://i.stack.imgur.com/1GCbd.png "click to enlarge")

_{Testing arguments containing Ranges vs. Arrays}<br>
[<img src="https://i.stack.imgur.com/4elJv.png" width="500" />](https://i.stack.imgur.com/fLduy.png "click to enlarge")

Note About Blank Cells

1. In the formulas above, blank cells are interpreted as zero
2. NETWORKDAYS will interpret zero as the numeric equivalent of 1/0/1900
3. The numeric equivalent of a date d can be determined by counting the number of days between d and 1/0/1900 which is the equivalent of VALUE(d)
4. As a result, NETWORKDAYS will return 0 if both the argument cells are blank, and will still return a number if one of the cells is blank (positive or negative depending on which argument is zero).

Workaround

The workaround is to coerce zero values (blank cells) to an error

1. NETWORKDAYS will return an error if either argument provided to it is an error
2. Dividing one by the inverse of a number n will return n where n<>0 but if n=0 it will trigger an error: 1/(1/3)=3 but 1/(1/0)=#DIV/0!
3. IFERROR will pass non-errors, but allow a different result if it detects an error. In the formula below the alternative result is blank, "", but it could easily be "Argument(s) Missing"

Formula with Workaround

=IFERROR(NETWORKDAYS(1/(1/Details[Date1]),1/(1/Details[Date2])),"")

Multi-Line Version

=IFERROR(
  NETWORKDAYS(
    1/(1/Details[Date1]),
    1/(1/Details[Date2])),"")