I have a series of dates (kept as date, month, and year) located in columns K to Z in Microsoft Excel. There are a different amount of dates in each row. I need a formula/code (not PivotTable) to:

  1. Find if any of these dates exist within 30 days (or x number of days) of others in the date range
  2. Find the difference in days between the two closest dates

There have been similar examples, but they haven't used the data range as the condition, so I've been getting error messages.
The following is an excerpt of data from columns K3:U8.
30/09/2016 24/08/2016 10/08/2016 20/07/2016 22/06/2016 8/06/2016 25/05/2016 27/04/2016 13/04/2016 30/03/2016
27/06/2016 13/06/2016 30/05/2016 16/05/2016 2/05/2016 18/04/2016 4/04/2016 14/03/2016 29/02/2016 16/02/2016
21/06/2016 16/05/2016 19/04/2016 15/03/2016
5/12/2016 14/11/2016 2/11/2016 17/10/2016 3/10/2016 19/09/2016 5/09/2016 15/08/2016 8/08/2016 25/07/2016 11/07/2016
14/12/2016 16/11/2016 2/11/2016 23/08/2016 26/07/2016
13/12/2016 29/11/2016 18/10/2016 23/08/2016 19/07/2016