Finding the free project dates

Nasir@EBC

Hi 

I am running a number of tasks in a sheet, with each task having its own Start and Finish date. 

What I need to find out, is a "free" period when there is absolutely no task running. 

Example:

Task A is from Jan 1 to 10;

Task B is from Jan 5 to 12;

Task C is from Jan 16 to 20; 

Task D is from Jan 15 to 25; 

and so on....

In the above example, the free period is from Jan 13 to 14 as none of the task-dates falls within this time window! 

Is there any way to find out all such "free" dates --either individually or collectively?

 

Please help! 

 

Paul Newcome

The first thing that comes to mind for me would be to use a date column to replicate each day of the month [Date Check]. Then I would add a checkbox column [Free Date].

 

In the checkbox column you could use a formula such as 

 

=IF(COUNTIFS([Start Date]:[Start Date], @cell <= [Date Check]@row, [End Date]:[End Date], @cell >= [Date Check]@row) = 0, 1)

.

First this will count how many rows have a start/end date that overlaps the date in question. If that count is zero, then no dates overlap making it a free date and checking the box.

.

There are a lot of different ways to collect those free dates for display.