Strategy. Vanguard Variable Insurance Funds High Yield Bond Portfolio (the Portfolio) invests primarily in a diversified group of high-yielding, higher-risk corporate bondscommonly known as junk bondswith medium- and lower-range credit quality ratings. Under normal circumstances, the Portfolio invests at least 80% of its assets in corporate bonds that are rated below Baa by Moodys Ratings; have an equivalent rating by any other independent bond rating agency; or, if unrated, are determined to be of comparable quality by the Portfolios advisors. The Portfolio may not invest more than 20% of its assets in any of the following, in the aggregate: bonds with credit ratings lower than B or the equivalent, convertible securities, preferred stocks, and fixed- and floating-rate loans of medium- to … Show more… Vanguard Variable Insurance Funds High Yield Bond Portfolio (the Portfolio) invests primarily in a diversified group of high-yielding, higher-risk corporate bondscommonly known as junk bondswith medium- and lower-range credit quality ratings. Under normal circumstances, the Portfolio invests at least 80% of its assets in corporate bonds that are rated below Baa by Moodys Ratings; have an equivalent rating by any other independent bond rating agency; or, if unrated, are determined to be of comparable quality by the Portfolios advisors. The Portfolio may not invest more than 20% of its assets in any of the following, in the aggregate: bonds with credit ratings lower than B or the equivalent, convertible securities, preferred stocks, and fixed- and floating-rate loans of medium- to lower-range credit quality. The loans in which the Portfolio may invest will be rated Baa or below by Moodys Ratings; have an equivalent rating by any other independent bond rating agency; or, if unrated, are determined to be of comparable quality by the Portfolios advisors. The Portfolio seeks to invest mostly in high-yield bonds and loans that have short- and intermediate-term maturities. Show less