MEGBX vs. VFIAX

Last updated Jun 5, 2026

MEGBX (MFS Growth Fund) and VFIAX (Vanguard 500 Index Fund Admiral Shares) are both mutual funds - MEGBX is a Large Cap Growth Equities fund managed by MFS, while VFIAX is a S&P 500 fund tracking the S&P 500 Index. Over the past 10 years, MEGBX returned 17.33%/yr vs 15.54%/yr for VFIAX. Their correlation of 0.92 suggests significant overlap in exposure. MEGBX charges 1.59%/yr vs 0.04%/yr for VFIAX.

Performance

MEGBX vs. VFIAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS Growth Fund (MEGBX) and Vanguard 500 Index Fund Admiral Shares (VFIAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MEGBX achieves a 4.50% return, which is significantly lower than VFIAX's 10.87% return. Over the past 10 years, MEGBX has outperformed VFIAX with an annualized return of 17.33%, while VFIAX has yielded a comparatively lower 15.54% annualized return.

MEGBX

• 1D: -1.27%
• 1M: 3.08%
• YTD: 4.50%
• 6M: 3.82%
• 1Y: 14.25%
• 3Y*: 28.40%
• 5Y*: 14.57%
• 10Y*: 17.33%

VFIAX

• 1D: -0.73%
• 1M: 4.17%
• YTD: 10.87%
• 6M: 10.78%
• 1Y: 27.99%
• 3Y*: 22.42%
• 5Y*: 13.87%
• 10Y*: 15.54%

*Multi-year figures are annualized to reflect compound growth (CAGR)

MEGBX vs. VFIAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MEGBX MFS Growth Fund	4.50%	11.25%	61.25%	34.81%	-31.83%	22.34%	30.36%	36.33%	1.21%	29.54%
VFIAX Vanguard 500 Index Fund Admiral Shares	10.87%	17.83%	24.97%	26.24%	-18.16%	28.65%	18.32%	31.46%	-4.45%	21.78%

Correlation

The correlation between MEGBX and VFIAX is 0.90, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.90
Correlation (3Y) Calculated over the trailing 3-year period	0.91
Correlation (5Y) Calculated over the trailing 5-year period	0.93
Correlation (10Y) Calculated over the trailing 10-year period	0.91
Correlation (All Time) Calculated using the full available price history since Nov 14, 2000	0.92

The correlation between MEGBX and VFIAX has been stable across timeframes, ranging from 0.90 to 0.93 - a consistent structural relationship.

Return for Risk

MEGBX vs. VFIAX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

MEGBX

MEGBX Risk / Return Rank: 11
MEGBX Sharpe Ratio Rank: 13
MEGBX Sortino Ratio Rank: 12
MEGBX Omega Ratio Rank: 12
MEGBX Calmar Ratio Rank: 9
MEGBX Martin Ratio Rank: 10

VFIAX

VFIAX Risk / Return Rank: 66
VFIAX Sharpe Ratio Rank: 64
VFIAX Sortino Ratio Rank: 59
VFIAX Omega Ratio Rank: 59
VFIAX Calmar Ratio Rank: 67
VFIAX Martin Ratio Rank: 79

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

MEGBX vs. VFIAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS Growth Fund (MEGBX) and Vanguard 500 Index Fund Admiral Shares (VFIAX). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	MEGBX	VFIAX	Difference
Sharpe ratio: Return per unit of total volatility	0.95	2.37	-1.42
Sortino ratio: Return per unit of downside risk	1.38	3.24	-1.86
Omega ratio: Gain probability vs. loss probability	1.17	1.43	-0.26
Calmar ratio: Return relative to maximum drawdown	0.86	3.16	-2.30
Martin ratio: Return relative to average drawdown	2.75	14.76	-12.02
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MEGBX vs. VFIAX - Sharpe Ratio Comparison

The current MEGBX Sharpe Ratio is 0.95, which is lower than the VFIAX Sharpe Ratio of 2.37. The chart below compares the historical Sharpe Ratios of MEGBX and VFIAX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	MEGBX	VFIAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.95	2.37	-1.42
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.62	0.83	-0.20
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.79	0.86	-0.07
Sharpe Ratio (All Time) Calculated using the full available price history	0.51	0.47	+0.04

Drawdowns

MEGBX vs. VFIAX - Drawdown Comparison

The maximum MEGBX drawdown since its inception was -72.95%, which is greater than VFIAX's maximum drawdown of -55.20%. Use the drawdown chart below to compare losses from any high point for MEGBX and VFIAX.

Drawdown Indicators

	MEGBX	VFIAX	Difference
Max Drawdown Largest peak-to-trough decline	-72.95%	-55.20%	-17.75%
Max Drawdown (1Y) Largest decline over 1 year	-17.64%	-8.90%	-8.74%
Max Drawdown (3Y) Largest decline over 3 years	-23.39%	-18.75%	-4.64%
Max Drawdown (5Y) Largest decline over 5 years	-36.73%	-24.53%	-12.20%
Max Drawdown (10Y) Largest decline over 10 years	-36.73%	-33.83%	-2.90%
Current Drawdown Current decline from peak	-1.61%	-0.73%	-0.88%
Average Drawdown Average peak-to-trough decline	-21.75%	-9.40%	-12.35%
Ulcer Index Depth and duration of drawdowns from previous peaks	5.48%	1.90%	+3.58%

Volatility

MEGBX vs. VFIAX - Volatility Comparison

MFS Growth Fund (MEGBX) has a higher volatility of 3.87% compared to Vanguard 500 Index Fund Admiral Shares (VFIAX) at 2.92%. This indicates that MEGBX's price experiences larger fluctuations and is considered to be riskier than VFIAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MEGBX	VFIAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.87%	2.92%	+0.95%
Volatility (6M) Calculated over the trailing 6-month period	12.30%	8.99%	+3.31%
Volatility (1Y) Calculated over the trailing 1-year period	15.88%	11.88%	+4.00%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	23.50%	16.90%	+6.60%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	22.04%	18.07%	+3.97%

MEGBX vs. VFIAX - Expense Ratio Comparison

MEGBX has a 1.59% expense ratio, which is higher than VFIAX's 0.04% expense ratio.

Dividends

MEGBX vs. VFIAX - Dividend Comparison

MEGBX's dividend yield for the trailing twelve months is around 25.45%, more than VFIAX's 1.02% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MEGBX MFS Growth Fund	25.45%	26.60%	40.46%	7.21%	1.51%	3.91%	4.94%	2.13%	4.95%	3.26%	2.03%	4.61%
VFIAX Vanguard 500 Index Fund Admiral Shares	1.02%	1.12%	1.24%	1.45%	1.68%	1.24%	1.53%	1.87%	2.05%	1.78%	2.02%	2.10%

Frequently Asked Questions

Can I hold both MEGBX and VFIAX in my portfolio?

With a correlation of 0.90, MEGBX and VFIAX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, MEGBX or VFIAX?

MEGBX has higher volatility (3.87%) compared to VFIAX (2.92%). In terms of maximum drawdown, MEGBX dropped -72.95% vs VFIAX's -55.20%.

Which has better risk-adjusted returns?

VFIAX currently has the higher Sharpe Ratio (2.37 vs 0.95), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.