Founded by John C. Bogle in 1975, Vanguard is one of the world's largest investment management companies. With around $3 trillion of assets under management, the company offers nearly 160 domestic funds and 120 funds for foreign markets (as of Dec 31, 2014). It offers asset management and financial planning services to clients throughout the globe.

Vanguard stands out from other mutual fund companies because it is owned by the funds themselves. The company believes that this structure helps management focus better on shareholder interests. Among the advantages Vanguard claims to offer are low-cost, no-load funds.

Below we share with you four top-rated Vanguard mutual funds. Each has earned a Zacks Mutual Fund Rank #1 (Strong Buy) and we expect the fund to outperform its peers in the future. To view the Zacks Rank and past performance of all Vanguard mutual funds, investors can click here to see the complete list of Vanguard funds .

Vanguard US Growth Investor (VWUSX - MF report) invests primarily in securities of companies located in the U.S. VWUSX focuses on acquiring common stocks of companies having large-cap market capitalizations. VWUSX considers companies with strong earnings growth prospects and favorable valuation for potential investment. The Vanguard US Growth Investor fund has a three-year annualized return of 12.7%.

VWUSX has an expense ratio of 0.47% as compared to the category average of 1.17%.

Vanguard Morgan Growth Investor (VMRGX - MF report) seeks capital appreciation over the long run. VMRGX uses multiple advisors to invest in domestic companies that are believed to provide above-average revenues and earnings growth. VMRGX invests in securities of companies having large and medium sized market capitalizations. The Vanguard Morgan Growth Investor fund has a three-year annualized return of 11%.

As of March 2016, VMRGX held 317 issues, with 4.77% of its total assets invested in Apple Inc.

Vanguard Strategic Equity Investor (VSEQX - MF report) invests a large portion of its assets in equity securities. VSEQX invests in both small- and mid-capitalization domestic equity securities. VSEQX selects securities that provide a balance between strong growth and reasonable valuations compared to industry peers. The Vanguard Strategic Equity Investor fund has a three-year annualized return of 10.2%.

VSEQX has an expense ratio of 0.21% as compared to the category average of 1.16%.

Vanguard New York Long-Term Tax-Exempt Investor (VNYTX - MF report) seeks tax-exempted current income. VNYTX generally invests in municipal debt securities of New York state, local governments and other affiliates. VNYTX invests a major portion of its assets in securities that are expected to provide return free from federal and New York state taxes. VNYTX generally maintains a dollar-weighted average maturity between 10 and 25 years. The Vanguard New York Long-Term Tax-Exempt Investor fund has a three-year annualized return of 4.7%.

Adam M. Ferguson is the fund manager of VNYTX since 2013.