Royal Dutch Shell is one of the largest energy companies in the world.

http://www.shell.com

It has two share classes, Shell A for Dutch shareholders and Shell B for UK Shareholders.

http://www.shareshop.hsbc.co.uk/shareshop/security.cgi?csi=133655
[Shell A]

http://www.shareshop.hsbc.co.uk/shareshop/security.cgi?csi=133755
[Shell B]

Look at the revenues:-

31-Dec-11 $470,171 Million
31-Dec-12 $467,153 Million
31-Dec-13 $451,235 Million
31-Dec-14 $421,105 Million
31-Dec-15 $264,960 Million

One can see year on year, the effect of falling energy prices affecting the revenues of Royal Dutch Shell