If Data in Column appears within Date Range then highlight

Question

I would like to do some conditional formatting on a Project Planner that will highlight a persons name if the dates selected for an activity to which they are assigned fall within a date range for another action to which they are also assigned.

On my spreadsheet I have the following columns:

• Column A: Activity
• Column B: Start Date
• Column C: End Date
• Column D: Responsible Person

To give an example of how I would like the formula to work:

Person A has been assigned an activity that begins on 01/02/14 and ends on 07/02/14. If a subsequent activity is then added to the sheet that either begins or ends on any of the dates within the range 01/02/14-07/02/14 and the person is assigned to it, i would like to use conditional formatting to highlight the cell as a sign to the user.

Any help would be appreciated.

Thanks,

Ryan

Answer 1

You could maybe use COUNTIFS with the conditional formatting:

=COUNTIFS(D:D,D1,B:B,"<="&C1,C:C,">="&B1)>1

This counts all the instances where the following conditions are satisfied:

1. The responsible person is the same person ( D:D, D1 part)

2. The dates the other activities begin are before or equal to the date a certain activity ends. ( B:B,"<="&C1 part)

3. The dates the other activities end are equal or after to the date a certain activity begins. ( C:C,">="&B1 part)

The formula can make Excel respond quite slowly since it takes into consideration the whole column. Change it to a range if possible, for example, if you always have about 100 activities, you could maybe use:

=COUNTIFS(D1:D120,D1,B1:B120,"<="&C1,C1:C120,">="&B1)>1

Here is what I get after using this conditional formatting:

COUNTIFS returns a number; a count of cells that satisfies the conditions. Since we have >1 at the end, this means that the cell(s) will get highlighted if there is more than one cell with the same conditions.