Two years ago, we first met with Pacer ETFs, a boutique Pennsylvania-based investment firm. After multiple meetings and extensive due diligence, we added their US Cash Cows 100 ETF (symbol: COWZ) to our investment models. This fund owns the 100 American companies with the highest free cash flow yield. Our conviction in this investment metric has grown over the past two years. Accordingly, we recently added two more "Cash Cow" funds to client portfolios.