OILD is an exchange-traded note that aims to deliver three times the inverse of the daily performance of an index composed of U.S. oil and gas companies. This geared product focuses on a concentrated selection of firms engaged in integrated exploration and production, upstream energy, and downstream/midstream operations, explicitly excluding Master Limited Partnerships (MLPs). The underlying index selects its top 25 constituents based on market capitalization, then applies a weighting methodology using their average daily trading value over one-month and six-month periods.