Date Calculation


=IFERROR(NETWORKDAYS([NAI Project Start Date]7, [NAI Project End Date]7), 0)


Cannot get this to calculate 


The first field has =Another_Cell but the property is set to date.  Is this the problem?


Im testing the date in the C1 field for being a date with NOPE being the return if its not a date

Screen Shot 07-25-18 at 02.30 PM.PNG



  • Shaine Greenwood

    Hi Manuel,

    I think that the columns you've got dates in isn't set to a Date column type. Try right-clicking the column header and selecting Column Properties, then switching them both to Date type columns. Leave the column you're putting your formula in as a Text/Number column.

  • Manuel Arrington

    So, I found that the date entry in the first column of 7/1/2018 is not a date.  I changed it to 7/1/18 and I got further with the calculation.


    Both Columns are set to date.  Interestingly I changed all of the 7/1/2018 to 7/1/18 and some work now and some don’t in the Networkdays calculation. Getting invalid type on some entries.

  • J. Craig Williams
    J. Craig Williams ✭✭✭✭✭✭

    You are getting #INVALID DATA TYPE even after using IFERROR()?

    NETWORKDAYS throws an error if either date is blank.


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