Excel Data Match Sheets

Registration date
Thursday February 19, 2015
Last seen
March 5, 2015
I am hoping you can please help me with a query in excel that I am stuck on.
I have 2 workbooks, one with raw data the other used for reporting. The workbook with the raw data has 2 columns one being publication number and the other column contains a figure that measures how many people see the publication. The other workbook we report any feature we get in the publication and manually enter the figure that corresponds with that publication that appears in the other workbook. Is there a way I can have this figure automatically filled in by using a formula?

Thanks for any help you can offer.