Strategy. To pursue its goal, the fund normally invests substantially all of its assets in bonds comprising the Bloomberg US Aggregate Total Return Index (index), and TBA transactions (as defined below) representing bonds included in the index. Under normal circumstances, the fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in bonds, TBA transactions representing bonds and ETFs providing exposure to such securities. The Bloomberg US Aggregate Total Return Index is designed to measure the investment grade, U.S. dollar-denominated, fixed-rate taxable bond market. The index includes Treasuries, government-related and corporate securities, mortgage-backed pass-through securities (agency fixed-rate), commercial mortgage-backed securities (agency and non-agency) and other asset-backed securities having at least one year until final maturity. … Show more… To pursue its goal, the fund normally invests substantially all of its assets in bonds comprising the Bloomberg US Aggregate Total Return Index (index), and TBA transactions (as defined below) representing bonds included in the index. Under normal circumstances, the fund will invest at least 80% of its net assets, plus any borrowings for investment purposes, in bonds, TBA transactions representing bonds and ETFs providing exposure to such securities. The Bloomberg US Aggregate Total Return Index is designed to measure the investment grade, U.S. dollar-denominated, fixed-rate taxable bond market. The index includes Treasuries, government-related and corporate securities, mortgage-backed pass-through securities (agency fixed-rate), commercial mortgage-backed securities (agency and non-agency) and other asset-backed securities having at least one year until final maturity. Treasury, government-related and corporate securities must have $300 million or more par amount outstanding. For mortgage-backed pass-through securities, pool aggregates must have $1 billion or more par amount outstanding. Asset-backed securities must have a minimum deal size of $500 million and a minimum tranche size of $25 million. Commercial mortgage-backed securities must have a minimum deal size of $500 million with at least $300 million outstanding and a minimum tranche size of $25 million. To be included in the index, securities must be rated investment grade (Baa3/BBB-/BBB- or higher) using the middle rating of Moody's, S&P and Fitch. When a rating from only two agencies is available, the lower is used; when only one agency rates a bond, that rating is used. In cases where explicit bond level ratings may not be available, the index provider may use other sources to classify securities by credit quality. The index may include U.S. dollar-denominated bonds issued by foreign issuers. Securities in the index are updated on the last business day of each month. The fund seeks to maintain a dollar-weighted average maturity consistent with that of the index. As of December 31, 2025, the index was comprised of approximately 14,000 securities and had a dollar-weighted average maturity of 8.16 years. Under normal circumstances, in seeking to track the index's performance, the fund generally purchases a representative sample of the securities comprising the index. By using a sampling process, the fund typically will not invest in all of the securities in the index. The fund may also fully replicate the index when determined to be in the best interest of the fund in pursuing its objective. In seeking to track the index, the funds assets may be concentrated in (i.e., more than 25% of the funds assets invested in) an industry or group of industries, but only to the extent that the index concentrates in a particular industry or group of industries. As of December 31, 2025, approximately 24% of the bonds represented in the index were U.S. agency mortgage-backed pass-through securities. U.S. agency mortgage-backed pass-through securities are securities issued by entities such as Government National Mortgage Association (GNMA) and Federal National Mortgage Association (FNMA) that are backed by pools of mortgages. Certain transactions in mortgage-backed pass-through securities occur through standardized contracts for future delivery in which the exact mortgage-backed pools to be delivered are not specified until a few days prior to settlement, referred to as a "to-be-announced transaction" or "TBA transaction." In a TBA transaction, the buyer and seller agree upon general trade parameters such as agency, settlement date, par amount and price. The actual pools delivered generally are determined two days prior to the settlement date. It is anticipated that the fund will generally participate in rolling TBA transactions, but it may also receive pools of mortgages. The fund expects to enter into TBA transactions on a regular basis. The fund, pending settlement of such contracts, will invest its assets in high-quality, liquid short term instruments, including shares of affiliated money market funds. The fund is classified as diversified under the Investment Company Act of 1940, as amended (1940 Act); however, the fund may become non-diversified solely as a result of changes in the composition of the index (e.g., changes in weightings of one or more component securities). When the fund is non-diversified, it may invest a relatively high percentage of its assets in a limited number of issuers. Show less