Express counted cells as % & change title color

[Red]

Hi,
I have a work rota spreadsheet, in each column there may be a number of V's indicating an employee's day vacation. I have worked out a formula to count these V's, =COUNTIF(D7:D56,"V") but I want to be able to change the column title, D5 to red if the number of V's exceed 14% of the blank cells between D7:D56. In other words, no more than 14% of the workforce can be on vaction at any one time and I want a quick visual indication. I think conditional formatting is in there somewhere, but I can't figure this one out.
Anybody any ideas please,
Thanks,
Red

 

[Andrew Poulsom]

Conditional Format formula in D5:

=COUNTIF(D7:D56,"V")/ROWS(D7:D56)>14%

 

[Sourdust]

Conditional Formatting in cell D5:
Formula is =(the cell with your Countif total)>14
then format the pattern to red

 

[Red]

Thanks Andrew & Sourdust,
Ticketyboo!
Red