VOO vs. MRK

Last updated Jun 9, 2026

VOO (Vanguard S&P 500 ETF) is S&P 500 fund tracking the S&P 500 Index, while MRK (Merck & Co., Inc.) is a stock. Over the past 10 years, VOO returned 15.35%/yr vs 11.61%/yr for MRK. At a 0.40 correlation, their price movements are largely independent.

Performance

VOO vs. MRK - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard S&P 500 ETF (VOO) and Merck & Co., Inc. (MRK). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VOO achieves a 8.72% return, which is significantly lower than MRK's 14.39% return. Over the past 10 years, VOO has outperformed MRK with an annualized return of 15.35%, while MRK has yielded a comparatively lower 11.61% annualized return.

VOO

• 1D: 0.25%
• 1M: 0.24%
• YTD: 8.72%
• 6M: 8.77%
• 1Y: 24.91%
• 3Y*: 21.45%
• 5Y*: 13.49%
• 10Y*: 15.35%

MRK

• 1D: -1.05%
• 1M: 7.31%
• YTD: 14.39%
• 6M: 22.75%
• 1Y: 56.85%
• 3Y*: 5.78%
• 5Y*: 13.57%
• 10Y*: 11.61%

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

VOO vs. MRK - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VOO Vanguard S&P 500 ETF	8.72%	17.82%	24.98%	26.32%	-18.17%	28.79%	18.32%	31.37%	-4.50%	21.77%
MRK Merck & Co., Inc.	14.39%	9.79%	-6.26%	1.01%	49.42%	1.75%	-7.20%	22.27%	39.95%	-1.49%

Correlation

The correlation between VOO and MRK is 0.14, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.14
Correlation (3Y) Calculated over the trailing 3-year period	0.11
Correlation (5Y) Calculated over the trailing 5-year period	0.16
Correlation (10Y) Calculated over the trailing 10-year period	0.29
Correlation (All Time) Calculated using the full available price history since Sep 10, 2010	0.40

Over the past year, the correlation between VOO and MRK has dropped to 0.14 - well below their long-term average of 0.40, suggesting their price drivers have been diverging.

Return for Risk

VOO vs. MRK — Risk / Return Rank

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

VOO

VOO Risk / Return Rank: 69
VOO Sharpe Ratio Rank: 71
VOO Sortino Ratio Rank: 68
VOO Omega Ratio Rank: 71
VOO Calmar Ratio Rank: 62
VOO Martin Ratio Rank: 75

MRK

MRK Risk / Return Rank: 90
MRK Sharpe Ratio Rank: 90
MRK Sortino Ratio Rank: 90
MRK Omega Ratio Rank: 86
MRK Calmar Ratio Rank: 92
MRK Martin Ratio Rank: 91

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.

VOO vs. MRK - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard S&P 500 ETF (VOO) and Merck & Co., Inc. (MRK). 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.

	VOO	MRK	Difference
Sharpe ratio: Return per unit of total volatility	2.08	2.10	-0.02
Sortino ratio: Return per unit of downside risk	2.80	3.05	-0.25
Omega ratio: Gain probability vs. loss probability	1.38	1.36	+0.01
Calmar ratio: Return relative to maximum drawdown	2.81	5.03	-2.22
Martin ratio: Return relative to average drawdown	12.97	12.59	+0.38
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VOO vs. MRK - Sharpe Ratio Comparison

The current VOO Sharpe Ratio is 2.08, which is comparable to the MRK Sharpe Ratio of 2.10. The chart below compares the historical Sharpe Ratios of VOO and MRK, 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

	VOO	MRK	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.08	2.10	-0.02
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.80	0.58	+0.23
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.85	0.51	+0.35
Sharpe Ratio (All Time) Calculated using the full available price history	0.88	0.48	+0.39

Drawdowns

VOO vs. MRK - Drawdown Comparison

The maximum VOO drawdown since its inception was -33.99%, smaller than the maximum MRK drawdown of -68.61%. Use the drawdown chart below to compare losses from any high point for VOO and MRK.

Drawdown Indicators

	VOO	MRK	Difference
Max Drawdown Largest peak-to-trough decline	-33.99%	-68.61%	+34.62%
Max Drawdown (1Y) Largest decline over 1 year	-8.90%	-11.37%	+2.47%
Max Drawdown (3Y) Largest decline over 3 years	-18.69%	-43.44%	+24.75%
Max Drawdown (5Y) Largest decline over 5 years	-24.52%	-43.44%	+18.92%
Max Drawdown (10Y) Largest decline over 10 years	-33.99%	-43.44%	+9.45%
Current Drawdown Current decline from peak	-2.66%	-4.65%	+1.99%
Average Drawdown Average peak-to-trough decline	-3.69%	-18.84%	+15.15%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.92%	4.53%	-2.61%

Volatility

VOO vs. MRK - Volatility Comparison

The current volatility for Vanguard S&P 500 ETF (VOO) is 3.73%, while Merck & Co., Inc. (MRK) has a volatility of 9.44%. This indicates that VOO experiences smaller price fluctuations and is considered to be less risky than MRK based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VOO	MRK	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.73%	9.44%	-5.71%
Volatility (6M) Calculated over the trailing 6-month period	9.31%	18.14%	-8.83%
Volatility (1Y) Calculated over the trailing 1-year period	12.08%	27.30%	-15.22%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.85%	23.71%	-6.86%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.03%	22.96%	-4.93%

Dividends

VOO vs. MRK - Dividend Comparison

VOO's dividend yield for the trailing twelve months is around 1.05%, less than MRK's 2.78% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MRK Merck & Co., Inc.	2.78%	3.12%	3.14%	2.72%	2.52%	3.41%	3.03%	2.48%	2.60%	3.36%	3.14%	3.43%
VOO Vanguard S&P 500 ETF	1.05%	1.13%	1.24%	1.46%	1.69%	1.25%	1.54%	1.88%	2.06%	1.78%	2.02%	2.10%

Frequently Asked Questions

Can I hold both VOO and MRK in my portfolio?

VOO and MRK have a correlation of 0.14, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, VOO or MRK?

MRK has higher volatility (9.44%) compared to VOO (3.73%). In terms of maximum drawdown, VOO dropped -33.99% vs MRK's -68.61%.

Which has better risk-adjusted returns?

MRK currently has the higher Sharpe Ratio (2.10 vs 2.08), 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.