ALT vs. VOO

Last updated Apr 1, 2026

Compare and contrast key facts about Altimmune, Inc. (ALT) and Vanguard S&P 500 ETF (VOO).

VOO is a passively managed fund by Vanguard that tracks the performance of the S&P 500 Index. It was launched on Sep 7, 2010.

Performance

ALT vs. VOO - Performance Comparison

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

ALT vs. VOO - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
ALT Altimmune, Inc.	-14.68%	-49.93%	-35.91%	-31.61%	79.59%	-18.79%	496.83%	-8.25%	-96.55%	-93.83%
VOO Vanguard S&P 500 ETF	-4.42%	17.82%	24.98%	26.32%	-18.17%	28.79%	18.32%	31.37%	-4.50%	21.77%

Returns By Period

In the year-to-date period, ALT achieves a -14.68% return, which is significantly lower than VOO's -4.42% return. Over the past 10 years, ALT has underperformed VOO with an annualized return of -40.86%, while VOO has yielded a comparatively higher 14.05% annualized return.

ALT

• 1D: 6.94%
• 1M: -28.54%
• YTD: -14.68%
• 6M: -18.30%
• 1Y: -38.40%
• 3Y*: -9.96%
• 5Y*: -26.13%
• 10Y*: -40.86%

VOO

• 1D: 2.86%
• 1M: -5.01%
• YTD: -4.42%
• 6M: -1.84%
• 1Y: 17.67%
• 3Y*: 18.27%
• 5Y*: 11.75%
• 10Y*: 14.05%

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

Return for Risk

ALT vs. VOO — Risk / Return Rank

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

ALT

ALT Risk / Return Rank: 26
ALT Sharpe Ratio Rank: 23
ALT Sortino Ratio Rank: 31
ALT Omega Ratio Rank: 32
ALT Calmar Ratio Rank: 18
ALT Martin Ratio Rank: 24

VOO

VOO Risk / Return Rank: 65
VOO Sharpe Ratio Rank: 59
VOO Sortino Ratio Rank: 62
VOO Omega Ratio Rank: 66
VOO Calmar Ratio Rank: 65
VOO Martin Ratio Rank: 75

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.

ALT vs. VOO - Risk-Adjusted Trends Comparison

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

	ALT	VOO	Difference
Sharpe ratio Return per unit of total volatility	-0.41	0.98	-1.39
Sortino ratio Return per unit of downside risk	0.05	1.50	-1.44
Omega ratio Gain probability vs. loss probability	1.01	1.23	-0.22
Calmar ratio Return relative to maximum drawdown	-0.67	1.53	-2.21
Martin ratio Return relative to average drawdown	-1.02	7.29	-8.32
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

ALT vs. VOO - Sharpe Ratio Comparison

The current ALT Sharpe Ratio is -0.41, which is lower than the VOO Sharpe Ratio of 0.98. The chart below compares the historical Sharpe Ratios of ALT and VOO, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	ALT	VOO	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	-0.41	0.98	-1.39
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.28	0.70	-0.98
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	-0.29	0.78	-1.07
Sharpe Ratio (All Time) Calculated using the full available price history	-0.24	0.83	-1.07

Correlation

The correlation between ALT and VOO is 0.21, which is considered to be low. This implies their price changes are not closely related. A low correlation is generally favorable for portfolio diversification, as it helps to reduce overall risk by spreading it across multiple assets with different performance patterns.

Dividends

ALT vs. VOO - Dividend Comparison

ALT has not paid dividends to shareholders, while VOO's dividend yield for the trailing twelve months is around 1.19%.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ALT Altimmune, Inc.	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
VOO Vanguard S&P 500 ETF	1.19%	1.13%	1.24%	1.46%	1.69%	1.25%	1.54%	1.88%	2.06%	1.78%	2.02%	2.10%

Drawdowns

ALT vs. VOO - Drawdown Comparison

The maximum ALT drawdown since its inception was -99.94%, which is greater than VOO's maximum drawdown of -33.99%. Use the drawdown chart below to compare losses from any high point for ALT and VOO.

Drawdown Indicators

	ALT	VOO	Difference
Max Drawdown Largest peak-to-trough decline	-99.94%	-33.99%	-65.95%
Max Drawdown (1Y) Largest decline over 1 year	-62.65%	-11.98%	-50.67%
Max Drawdown (5Y) Largest decline over 5 years	-90.45%	-24.52%	-65.93%
Max Drawdown (10Y) Largest decline over 10 years	-99.85%	-33.99%	-65.86%
Current Drawdown Current decline from peak	-99.89%	-6.29%	-93.60%
Average Drawdown Average peak-to-trough decline	-80.66%	-3.72%	-76.94%
Ulcer Index Depth and duration of drawdowns from previous peaks	41.12%	2.52%	+38.60%

Volatility

ALT vs. VOO - Volatility Comparison

Altimmune, Inc. (ALT) has a higher volatility of 26.59% compared to Vanguard S&P 500 ETF (VOO) at 5.29%. This indicates that ALT's price experiences larger fluctuations and is considered to be riskier than VOO based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	ALT	VOO	Difference
Volatility (1M) Calculated over the trailing 1-month period	26.59%	5.29%	+21.30%
Volatility (6M) Calculated over the trailing 6-month period	58.39%	9.44%	+48.95%
Volatility (1Y) Calculated over the trailing 1-year period	93.96%	18.10%	+75.86%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	94.38%	16.82%	+77.56%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	142.47%	17.99%	+124.48%