PXI follows a Dorsey Wright relative strength index that selects and weights US energy stocks by price momentum. Index construction begins by assigning a momentum score to the 2,000 largest constituents from the NASDAQ US Benchmark index. The score is based on upward price movements of the security compared to the benchmark and other eligible securities within the universe. The top 30 highest momentum-scoring stocks in the energy sector are then chosen for the index with higher scoring securities receiving greater weight. The portfolio tilts small, with a growth bias and somewhat higher risk. The index is reconstituted and rebalanced quarterly. Prior to August 28, 2023, the ETF's name was Invesco DWA Energy Momentum ETF.