Strategy. The Fund normally invests at least 80% of its net assets plus any borrowings for investment purposes (measured at the time of investment) in equity securities. Equity securities include common stocks and other securities that represent an ownership interest (or right to acquire an ownership interest) in a company or other issuer. Massachusetts Financial Services Company (MFS), the Fund's subadviser (the "Subadviser"), may invest the Fund's assets in securities of companies of any size and in foreign securities. In selecting investments for the Fund, the Subadviser is not constrained by any particular investment style. The Subadviser may invest the Fund's assets in the stocks of companies it believes to have above average earnings growth potential compared to other companies (growth … Show more… The Fund normally invests at least 80% of its net assets plus any borrowings for investment purposes (measured at the time of investment) in equity securities. Equity securities include common stocks and other securities that represent an ownership interest (or right to acquire an ownership interest) in a company or other issuer. Massachusetts Financial Services Company (MFS), the Fund's subadviser (the "Subadviser"), may invest the Fund's assets in securities of companies of any size and in foreign securities. In selecting investments for the Fund, the Subadviser is not constrained by any particular investment style. The Subadviser may invest the Fund's assets in the stocks of companies it believes to have above average earnings growth potential compared to other companies (growth companies), in the stocks of companies it believes are undervalued compared to their perceived worth (value companies), or in a combination of growth and value companies. The Subadviser normally invests the Fund's assets across different industries and sectors, but the Subadviser may invest a significant percentage of the Fund's assets in issuers in a single industry or sector. The Subadviser may also invest a significant percentage of the Fund's assets in issuers in a single country or geographic region. A team of investment research analysts selects investments for the Fund. The Subadviser generally expects the Fund's exposure to broad industry categories to approximate the exposure of the Russell 3000 Index (the "Index") to these broad industry categories using the Subadviser's custom industry categories to classify the Fund and the Index's holdings. The Subadviser uses an active bottom-up investment approach to buying and selling investments for the Fund. Investments are selected primarily based on fundamental analysis of individual issuers and their potential in light of their financial condition, and market, economic, political, and regulatory conditions. Factors considered by the Subadviser may include analysis of an issuer's earnings, cash flows, competitive position, and management ability. The Subadviser may also consider environmental, social, and governance ("ESG") factors in its fundamental investment analysis where the Subadviser believes such factors could materially impact the economic value of an issuer. ESG factors considered may include, but are not limited to, climate change, resource depletion, an issuer's governance structure and practices, data protection and privacy issues, and diversity and labor practices. Quantitative screening tools that systematically evaluate an issuer's valuation, price and earnings momentum, earnings quality, and other factors, may also be considered by the Subadviser. Show less