The index is designed to provide exposure to leading partnerships that trade on major U.S. exchanges and are classified in the GICS Energy Sector and GICS Gas Utilities Industry according to the Global Industry Classification Standard ("GICS"). It includes both master limited partnerships ("MLPs") and publicly traded limited liability companies which have a similar legal structure to MLPs and share the same tax benefits as MLPs (collectively, the "index constituents"). The index is calculated, maintained and published by S&P Dow Jones Indices LLC.