The State Street SPDR Portfolio S&P 400 Mid Cap ETF seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of the S&P MidCap 400 Index (the "Index")A low-cost ETF that seeks to offer precise, comprehensive exposure to mid cap US equitiesThe Index is float-adjusted and market capitalization weightedOne of the low-cost core State Street SPDR Portfolio ETFs, a suite of portfolio building blocks designed to provide broad, diversified exposure to core asset classes