Importing data from excel to Outlook calendar

Hello

I would like to import -as the tittle says- data from an excel spreadsheet to the Outlook calender. Thatīs because I would like to give the people from our production center a more visual approach of what needs to be produced when. The problem I have is that I can match the excel columns with the outlooks calendar fields. Any ideas why this is happening? I attach an image so you can see better what my problem is.

Thanks in advance!