Cant group dates

Hi Friends, I am analyzing data in the excel. I have tried to group dates in vain. in a cell they are aligned in the left which i think excel recognize as text?. How can i convert to the normal dates so that i can group in months or years and make my charts awesome. thanks for your help

I also have % numbers with about five decimal places, when analyzing and want to group them, i received a message which says these cannot be grouped. Your guidance please

If you add a sample file as an attachment which what you require, it should not be too difficult to sort, but is it a one off or a recurring task.

I would also rename the post to something that better describes the problem. Convert text dates to dates to allow grouping or something along those lines