4 Mid-Cap Funds Using the AlphaDEX Approach First Trust Mid Cap Value AlphaDEX Fund (FNK): The fund will normally invest at least 90% of its net assets in the common stocks that comprise the index. Rising inflation and an ongoing pandemic can inject a heavy dose of volatility into the markets. The funds are designed to track the performance of a group of custom "enhanced" indexes which employ the proprietary, rules-based AlphaDEX fundamental stock selection methodology.