COWZ tracks the Pacer US Cash Cows 100 Index, which selects 100 companies from the Russell 1000, excluding financials and real estate, with the highest free cash flow yield, meaning free cash flow relative to enterprise value. The approach favors companies that generate substantial cash relative to their price, so the fund tends to hold more energy, healthcare, industrials and consumer companies and less technology than cap-weighted funds. The portfolio is reconstituted regularly and can change significantly from one period to the next.