If Statements, Dates, % and Blank Cells

[KarenH119]

Hello,
I am trying to figure out a way to for a cell to calculate the difference between two dates divided by the total days to = % of completion for a project. In that same cell if there is no start or end date leave the cell blank, but if today date is greater than end date make the cell say 100%
I was trying the following formula but it was not doing everything I wanted.

Showing in cell H11
=IF(C11<=H$5,(IF(G11>=H$5,(H$5-C11)/(G11-C11),1))," ")

 

[RonB1111]

If start date is in C11 and end date is in G11, try:

=IF(OR(C11="",G11=""),"",IF(TODAY()>=G11,1,(TODAY()-C11)/(G11-C11)))

I didn't know what H5 represents. If the above doesn't work, please clarify H5.