PLUG vs. SOUN

Last updated Jun 9, 2026

PLUG (Plug Power Inc.) and SOUN (SoundHound AI, Inc.) are both stocks. PLUG operates in Electrical Equipment & Parts (Industrials), while SOUN operates in Software - Application (Technology). Over the past 3 years, PLUG returned -29.67%/yr vs 35.66%/yr for SOUN. At a 0.32 correlation, their price movements are largely independent.

Performance

PLUG vs. SOUN - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Plug Power Inc. (PLUG) and SoundHound AI, Inc. (SOUN). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, PLUG achieves a 61.93% return, which is significantly higher than SOUN's -24.87% return.

PLUG

• 1D: -0.78%
• 1M: 2.24%
• YTD: 61.93%
• 6M: 47.69%
• 1Y: 229.14%
• 3Y*: -29.67%
• 5Y*: -37.11%
• 10Y*: 5.89%

SOUN

• 1D: 1.35%
• 1M: -15.65%
• YTD: -24.87%
• 6M: -40.93%
• 1Y: -25.91%
• 3Y*: 35.66%
• 5Y*: —
• 10Y*: —

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

PLUG vs. SOUN - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022
PLUG Plug Power Inc.	61.93%	-7.51%	-52.67%	-63.62%	-44.10%
SOUN SoundHound AI, Inc.	-24.87%	-49.75%	835.85%	19.77%	-79.70%

Correlation

The correlation between PLUG and SOUN is 0.38, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.38
Correlation (3Y) Calculated over the trailing 3-year period	0.35
Correlation (All Time) Calculated using the full available price history since Apr 28, 2022	0.32

Fundamentals

Market Cap PLUG : $4.43B SOUN : $2.54B
EPS PLUG : -$1.39 SOUN : -$0.43
PS Ratio PLUG : 5.21 SOUN : 15.98
PB Ratio PLUG : 5.91 SOUN : 5.50
Total Revenue (TTM) PLUG : $739.76M SOUN : $183.99M
Gross Profit (TTM) PLUG : -$189.79M SOUN : $69.84M
EBITDA (TTM) PLUG : -$745.89M SOUN : -$124.47M

Return for Risk

PLUG vs. SOUN — Risk / Return Rank

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

PLUG

PLUG Risk / Return Rank: 87
PLUG Sharpe Ratio Rank: 90
PLUG Sortino Ratio Rank: 90
PLUG Omega Ratio Rank: 84
PLUG Calmar Ratio Rank: 89
PLUG Martin Ratio Rank: 82

SOUN

SOUN Risk / Return Rank: 31
SOUN Sharpe Ratio Rank: 28
SOUN Sortino Ratio Rank: 32
SOUN Omega Ratio Rank: 31
SOUN Calmar Ratio Rank: 30
SOUN Martin Ratio Rank: 31

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.

PLUG vs. SOUN - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Plug Power Inc. (PLUG) and SoundHound AI, Inc. (SOUN). 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.

	PLUG	SOUN	Difference
Sharpe ratio: Return per unit of total volatility	2.08	-0.32	+2.41
Sortino ratio: Return per unit of downside risk	3.13	0.02	+3.11
Omega ratio: Gain probability vs. loss probability	1.34	1.00	+0.34
Calmar ratio: Return relative to maximum drawdown	4.07	-0.36	+4.43
Martin ratio: Return relative to average drawdown	6.93	-0.58	+7.51
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

PLUG vs. SOUN - Sharpe Ratio Comparison

The current PLUG Sharpe Ratio is 2.08, which is higher than the SOUN Sharpe Ratio of -0.32. The chart below compares the historical Sharpe Ratios of PLUG and SOUN, 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

	PLUG	SOUN	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.08	-0.32	+2.41
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.39	—	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.07	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	-0.14	-0.00	-0.14

Drawdowns

PLUG vs. SOUN - Drawdown Comparison

The maximum PLUG drawdown since its inception was -99.99%, which is greater than SOUN's maximum drawdown of -93.55%. Use the drawdown chart below to compare losses from any high point for PLUG and SOUN.

Drawdown Indicators

	PLUG	SOUN	Difference
Max Drawdown Largest peak-to-trough decline	-99.99%	-93.55%	-6.44%
Max Drawdown (1Y) Largest decline over 1 year	-56.66%	-72.43%	+15.77%
Max Drawdown (3Y) Largest decline over 3 years	-94.69%	-75.65%	-19.04%
Max Drawdown (5Y) Largest decline over 5 years	-98.43%	—	—
Max Drawdown (10Y) Largest decline over 10 years	-99.04%	—	—
Current Drawdown Current decline from peak	-99.79%	-69.09%	-30.70%
Average Drawdown Average peak-to-trough decline	-96.23%	-66.95%	-29.28%
Ulcer Index Depth and duration of drawdowns from previous peaks	33.23%	44.50%	-11.27%

Volatility

PLUG vs. SOUN - Volatility Comparison

Plug Power Inc. (PLUG) has a higher volatility of 30.53% compared to SoundHound AI, Inc. (SOUN) at 19.06%. This indicates that PLUG's price experiences larger fluctuations and is considered to be riskier than SOUN based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	PLUG	SOUN	Difference
Volatility (1M) Calculated over the trailing 1-month period	30.53%	19.06%	+11.47%
Volatility (6M) Calculated over the trailing 6-month period	63.42%	51.57%	+11.85%
Volatility (1Y) Calculated over the trailing 1-year period	111.05%	80.46%	+30.59%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	94.50%	136.34%	-41.84%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	89.47%	136.34%	-46.87%

Dividends

PLUG vs. SOUN - Dividend Comparison

Neither PLUG nor SOUN has paid dividends to shareholders.

Tickers have no history of dividend payments

Financials

Frequently Asked Questions

Can I hold both PLUG and SOUN in my portfolio?

PLUG and SOUN have a correlation of 0.38, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, PLUG or SOUN?

PLUG has higher volatility (30.53%) compared to SOUN (19.06%). In terms of maximum drawdown, PLUG dropped -99.99% vs SOUN's -93.55%.

Which has better risk-adjusted returns?

PLUG currently has the higher Sharpe Ratio (2.08 vs -0.32), 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.