PXJ is a unique take on oil & gas services, following a multi-factor selection methodology with a tiered weighting scheme that creates a small-cap tilt. The fund offers a concentrated exposure to 30 US stocks, selected using quant screens based on five factors: price momentum, earnings momentum, quality, management action, and value. Historically, PXJ has heavily underweighted oil & gas transportation services, missing out on large pipeline operators. The indexs tier weighting reduces concentrations in mega-caps and evenly weights the group of companies across size. The fund and the index are rebalanced and reconstituted quarterly in February, May, August and November. Prior to August 28, 2023, the ETF's name was Invesco Dynamic Oil & Gas Services ETF.