PDFS vs. VOO

Last updated Jul 14, 2026

PDFS (PDF Solutions, Inc.) is a stock, while VOO (Vanguard S&P 500 ETF) is S&P 500 fund tracking the S&P 500 Index. Over the past 10 years, PDFS returned 13.57%/yr vs 15.20%/yr for VOO. A 0.55 correlation means they provide meaningful diversification when combined.

Performance

PDFS vs. VOO - Performance Comparison

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

Returns By Period

In the year-to-date period, PDFS achieves a 85.03% return, which is significantly higher than VOO's 10.87% return. Over the past 10 years, PDFS has underperformed VOO with an annualized return of 13.57%, while VOO has yielded a comparatively higher 15.20% annualized return.

PDFS

• 1D: -4.92%
• 1M: -17.70%
• 6M: 65.64%
• YTD: 85.03%
• 1Y: 129.32%
• 3Y*: 5.09%
• 5Y*: 24.16%
• 10Y*: 13.57%

VOO

• 1D: 0.38%
• 1M: 1.64%
• 6M: 8.98%
• YTD: 10.87%
• 1Y: 21.75%
• 3Y*: 20.31%
• 5Y*: 13.16%
• 10Y*: 15.20%

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

PDFS vs. VOO - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
PDFS PDF Solutions, Inc.	85.03%	5.35%	-15.74%	12.69%	-10.29%	47.18%	27.89%	100.36%	-46.31%	-30.38%
VOO Vanguard S&P 500 ETF	10.87%	17.82%	24.98%	26.32%	-18.17%	28.79%	18.32%	31.37%	-4.50%	21.77%

Correlation

The correlation between PDFS and VOO is 0.60, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.60
Correlation (3Y) Calculated over the trailing 3-year period	0.63
Correlation (5Y) Calculated over the trailing 5-year period	0.60
Correlation (10Y) Calculated over the trailing 10-year period	0.54
Correlation (All Time) Calculated using the full available price history since Sep 9, 2010	0.55

The correlation between PDFS and VOO has been stable across timeframes, ranging from 0.54 to 0.62 - a consistent structural relationship.

Return for Risk

PDFS vs. VOO — Risk / Return Rank

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

PDFS

PDFS Risk / Return Rank: 90
PDFS Sharpe Ratio Rank: 92
PDFS Sortino Ratio Rank: 87
PDFS Omega Ratio Rank: 87
PDFS Calmar Ratio Rank: 94
PDFS Martin Ratio Rank: 93

VOO

VOO Risk / Return Rank: 67
VOO Sharpe Ratio Rank: 67
VOO Sortino Ratio Rank: 66
VOO Omega Ratio Rank: 67
VOO Calmar Ratio Rank: 62
VOO Martin Ratio Rank: 73

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.

PDFS vs. VOO - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for PDF Solutions, Inc. (PDFS) 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	PDFS	VOO	Difference
Sharpe ratio: Return per unit of total volatility	2.10	1.75	+0.35
Sortino ratio: Return per unit of downside risk	2.50	2.41	+0.09
Omega ratio: Gain probability vs. loss probability	1.33	1.32	+0.01
Calmar ratio: Return relative to maximum drawdown	4.81	2.45	+2.35
Martin ratio: Return relative to average drawdown	12.41	10.70	+1.70

PDFS vs. VOO - Sharpe Ratio Comparison

The current PDFS Sharpe Ratio is 2.10, which is comparable to the VOO Sharpe Ratio of 1.75. The chart below compares the historical Sharpe Ratios of PDFS and VOO, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

PDFS vs. VOO - Drawdown Comparison

The maximum PDFS drawdown since its inception was -95.46%, which is greater than VOO's maximum drawdown of -33.99%. Use the drawdown chart below to compare losses from any high point for PDFS and VOO.

Drawdown Indicators

	PDFS	VOO	Difference
Max Drawdown Largest peak-to-trough decline	-95.46%	-33.99%	-61.47%
Max Drawdown (1Y) Largest decline over 1 year	-27.07%	-8.90%	-18.17%
Max Drawdown (3Y) Largest decline over 3 years	-64.59%	-18.69%	-45.90%
Max Drawdown (5Y) Largest decline over 5 years	-65.53%	-24.52%	-41.01%
Max Drawdown (10Y) Largest decline over 10 years	-68.00%	-33.99%	-34.01%
Current Drawdown Current decline from peak	-25.43%	-0.74%	-24.69%
Average Drawdown Average peak-to-trough decline	-43.93%	-3.67%	-40.26%
Ulcer Index Depth and duration of drawdowns from previous peaks	10.46%	2.04%	+8.42%

Volatility

PDFS vs. VOO - Volatility Comparison

PDF Solutions, Inc. (PDFS) has a higher volatility of 29.37% compared to Vanguard S&P 500 ETF (VOO) at 3.86%. This indicates that PDFS'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

	PDFS	VOO	Difference
Volatility (1M) Calculated over the trailing 1-month period	29.37%	3.86%	+25.51%
Volatility (6M) Calculated over the trailing 6-month period	50.62%	9.96%	+40.66%
Volatility (1Y) Calculated over the trailing 1-year period	62.14%	12.51%	+49.63%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	49.59%	16.93%	+32.66%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	46.85%	18.00%	+28.85%

Dividends

PDFS vs. VOO - Dividend Comparison

PDFS has not paid dividends to shareholders, while VOO's dividend yield for the trailing twelve months is around 1.06%.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PDFS PDF Solutions, 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	1.06%	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 PDFS and VOO in my portfolio?

PDFS and VOO have a correlation of 0.60, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, PDFS or VOO?

PDFS has higher volatility (29.37%) compared to VOO (3.86%). In terms of maximum drawdown, PDFS dropped -95.46% vs VOO's -33.99%.

Which has better risk-adjusted returns?

PDFS currently has the higher Sharpe Ratio (2.10 vs 1.75), 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.