I found a plug from Microsoft outlook which reduces these emails. This is a free plug-in available for users of Microsoft Outlook 2007, 2010 and 2013 which you can download from here.
After installing it, and restarting Outlook, you will be able to report Junk by right-clicking the email and selecting Junk à Report Junk
The software will do the rest for you.
Hope this helps!!
