VFIAX vs. MGK

Last updated Jun 9, 2026

VFIAX (Vanguard 500 Index Fund Admiral Shares) and MGK (Vanguard Mega Cap Growth ETF) are both funds - VFIAX is a S&P 500 fund tracking the S&P 500 Index, while MGK is a Large Cap Growth Equities fund tracking the CRSP US Mega Cap Growth Index. Both are passively managed. Over the past 10 years, VFIAX returned 15.21%/yr vs 18.91%/yr for MGK. Their correlation of 0.94 suggests significant overlap in exposure. VFIAX charges 0.04%/yr vs 0.05%/yr for MGK.

Performance

VFIAX vs. MGK - Performance Comparison

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

Returns By Period

In the year-to-date period, VFIAX achieves a 8.41% return, which is significantly higher than MGK's 6.52% return. Over the past 10 years, VFIAX has underperformed MGK with an annualized return of 15.21%, while MGK has yielded a comparatively higher 18.91% annualized return.

VFIAX

• 1D: -2.63%
• 1M: -0.08%
• YTD: 8.41%
• 6M: 8.46%
• 1Y: 24.51%
• 3Y*: 21.49%
• 5Y*: 13.36%
• 10Y*: 15.21%

MGK

• 1D: 0.45%
• 1M: -0.30%
• YTD: 6.52%
• 6M: 5.59%
• 1Y: 25.21%
• 3Y*: 25.50%
• 5Y*: 15.44%
• 10Y*: 18.91%

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

VFIAX vs. MGK - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VFIAX Vanguard 500 Index Fund Admiral Shares	8.41%	17.83%	24.97%	26.24%	-18.16%	28.65%	18.32%	31.46%	-4.45%	21.78%
MGK Vanguard Mega Cap Growth ETF	6.52%	20.67%	32.94%	51.67%	-33.59%	28.58%	41.01%	37.38%	-2.91%	29.49%

Correlation

The correlation between VFIAX and MGK is 0.91, 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	0.91
Correlation (3Y) Calculated over the trailing 3-year period	0.92
Correlation (5Y) Calculated over the trailing 5-year period	0.93
Correlation (10Y) Calculated over the trailing 10-year period	0.92
Correlation (All Time) Calculated using the full available price history since Dec 28, 2007	0.94

The correlation between VFIAX and MGK has been stable across timeframes, ranging from 0.91 to 0.94 - a consistent structural relationship.

VFIAX vs. MGK - Sectors Allocation Comparison

Sectors	VFIAX	MGK
Technology	35.7%	56.1%
Financial Services	11.6%	4.5%
Communication Services	11.3%	17.3%
Consumer Cyclical	10.2%	12.8%
Healthcare	8.5%	4.5%
Industrials	8.3%	1.1%
Consumer Defensive	4.9%	0.4%
Energy	3.5%	-
Utilities	2.4%	1.2%
Real Estate	1.9%	1.3%
Basic Materials	1.8%	0.7%

Return for Risk

VFIAX vs. MGK — Risk / Return Rank

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

VFIAX

VFIAX Risk / Return Rank: 59
VFIAX Sharpe Ratio Rank: 56
VFIAX Sortino Ratio Rank: 49
VFIAX Omega Ratio Rank: 53
VFIAX Calmar Ratio Rank: 62
VFIAX Martin Ratio Rank: 74

MGK

MGK Risk / Return Rank: 42
MGK Sharpe Ratio Rank: 48
MGK Sortino Ratio Rank: 47
MGK Omega Ratio Rank: 47
MGK Calmar Ratio Rank: 34
MGK Martin Ratio Rank: 36

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.

VFIAX vs. MGK - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard 500 Index Fund Admiral Shares (VFIAX) and Vanguard Mega Cap Growth ETF (MGK). 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.

	VFIAX	MGK	Difference
Sharpe ratio: Return per unit of total volatility	2.13	1.52	+0.60
Sortino ratio: Return per unit of downside risk	2.87	2.08	+0.79
Omega ratio: Gain probability vs. loss probability	1.39	1.27	+0.12
Calmar ratio: Return relative to maximum drawdown	2.91	1.50	+1.41
Martin ratio: Return relative to average drawdown	13.54	5.15	+8.39
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VFIAX vs. MGK - Sharpe Ratio Comparison

The current VFIAX Sharpe Ratio is 2.13, which is higher than the MGK Sharpe Ratio of 1.52. The chart below compares the historical Sharpe Ratios of VFIAX and MGK, 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

	VFIAX	MGK	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.13	1.52	+0.60
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.79	0.68	+0.11
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.84	0.87	-0.02
Sharpe Ratio (All Time) Calculated using the full available price history	0.46	0.65	-0.18

Drawdowns

VFIAX vs. MGK - Drawdown Comparison

The maximum VFIAX drawdown since its inception was -55.20%, which is greater than MGK's maximum drawdown of -47.97%. Use the drawdown chart below to compare losses from any high point for VFIAX and MGK.

Drawdown Indicators

	VFIAX	MGK	Difference
Max Drawdown Largest peak-to-trough decline	-55.20%	-47.97%	-7.23%
Max Drawdown (1Y) Largest decline over 1 year	-8.90%	-16.85%	+7.95%
Max Drawdown (3Y) Largest decline over 3 years	-18.75%	-23.36%	+4.61%
Max Drawdown (5Y) Largest decline over 5 years	-24.53%	-36.01%	+11.48%
Max Drawdown (10Y) Largest decline over 10 years	-33.83%	-36.01%	+2.18%
Current Drawdown Current decline from peak	-2.94%	-4.56%	+1.62%
Average Drawdown Average peak-to-trough decline	-9.39%	-7.47%	-1.92%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.91%	4.91%	-3.00%

Volatility

VFIAX vs. MGK - Volatility Comparison

The current volatility for Vanguard 500 Index Fund Admiral Shares (VFIAX) is 3.81%, while Vanguard Mega Cap Growth ETF (MGK) has a volatility of 5.41%. This indicates that VFIAX experiences smaller price fluctuations and is considered to be less risky than MGK based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VFIAX	MGK	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.81%	5.41%	-1.60%
Volatility (6M) Calculated over the trailing 6-month period	9.41%	12.96%	-3.55%
Volatility (1Y) Calculated over the trailing 1-year period	12.19%	16.65%	-4.46%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.93%	22.69%	-5.76%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.08%	21.92%	-3.84%

VFIAX vs. MGK - Expense Ratio Comparison

VFIAX has a 0.04% expense ratio, which is lower than MGK's 0.05% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

VFIAX vs. MGK - Dividend Comparison

VFIAX's dividend yield for the trailing twelve months is around 1.04%, more than MGK's 0.33% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MGK Vanguard Mega Cap Growth ETF	0.33%	0.35%	0.43%	0.50%	0.70%	0.41%	0.65%	0.85%	1.12%	1.23%	1.53%	1.43%
VFIAX Vanguard 500 Index Fund Admiral Shares	1.04%	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 VFIAX and MGK in my portfolio?

With a correlation of 0.91, VFIAX and MGK 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, VFIAX or MGK?

MGK has higher volatility (5.41%) compared to VFIAX (3.81%). In terms of maximum drawdown, VFIAX dropped -55.20% vs MGK's -47.97%.

Which has better risk-adjusted returns?

VFIAX currently has the higher Sharpe Ratio (2.13 vs 1.52), 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.