VSS vs. PDN

Last updated Jun 4, 2026

VSS (Vanguard FTSE All-World ex-US Small-Cap ETF) and PDN (Invesco FTSE RAFI Developed Markets ex-U.S. Small-Mid ETF) are both Foreign Small & Mid Cap Equities funds - VSS tracks the FTSE Global Small Cap ex US Index while PDN tracks the FTSE RAFI Developed x US Mid/Small. Both are passively managed. Over the past 10 years, VSS returned 8.07%/yr vs 8.41%/yr for PDN. Their correlation of 0.90 suggests significant overlap in exposure. VSS charges 0.07%/yr vs 0.49%/yr for PDN.

Performance

VSS vs. PDN - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard FTSE All-World ex-US Small-Cap ETF (VSS) and Invesco FTSE RAFI Developed Markets ex-U.S. Small-Mid ETF (PDN). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both stocks are quite close, with VSS having a 10.57% return and PDN slightly lower at 10.22%. Both investments have delivered pretty close results over the past 10 years, with VSS having a 8.07% annualized return and PDN not far ahead at 8.41%.

VSS

• 1D: -1.12%
• 1M: 1.27%
• YTD: 10.57%
• 6M: 13.10%
• 1Y: 27.32%
• 3Y*: 16.67%
• 5Y*: 5.76%
• 10Y*: 8.07%

PDN

• 1D: -0.74%
• 1M: 0.91%
• YTD: 10.22%
• 6M: 12.61%
• 1Y: 27.72%
• 3Y*: 18.02%
• 5Y*: 6.42%
• 10Y*: 8.41%

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

VSS vs. PDN - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VSS Vanguard FTSE All-World ex-US Small-Cap ETF	10.57%	29.61%	2.94%	15.52%	-21.48%	13.05%	11.81%	21.36%	-18.48%	30.61%
PDN Invesco FTSE RAFI Developed Markets ex-U.S. Small-Mid ETF	10.22%	38.34%	0.57%	13.35%	-17.35%	9.03%	10.65%	19.17%	-18.38%	30.74%

Correlation

The correlation between VSS and PDN is 0.95 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.95
Correlation (3Y) Calculated over the trailing 3-year period	0.94
Correlation (5Y) Calculated over the trailing 5-year period	0.95
Correlation (10Y) Calculated over the trailing 10-year period	0.94
Correlation (All Time) Calculated using the full available price history since Apr 7, 2009	0.90

The correlation between VSS and PDN has been stable across timeframes, ranging from 0.90 to 0.95 - a consistent structural relationship.

VSS vs. PDN - Sectors Allocation Comparison

Sectors	VSS	PDN
Industrials	18.7%	22.4%
Technology	13.3%	10.3%
Basic Materials	12.1%	10.0%
Financial Services	10.8%	11.4%
Consumer Cyclical	9.3%	11.1%
Real Estate	7.3%	8.6%
Healthcare	6.2%	5.4%
Energy	4.9%	5.1%
Consumer Defensive	3.4%	4.7%
Utilities	2.5%	2.4%
Communication Services	2.3%	3.3%

Return for Risk

VSS vs. PDN — Risk / Return Rank

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

VSS

VSS Risk / Return Rank: 51
VSS Sharpe Ratio Rank: 53
VSS Sortino Ratio Rank: 51
VSS Omega Ratio Rank: 54
VSS Calmar Ratio Rank: 47
VSS Martin Ratio Rank: 53

PDN

PDN Risk / Return Rank: 55
PDN Sharpe Ratio Rank: 56
PDN Sortino Ratio Rank: 56
PDN Omega Ratio Rank: 56
PDN Calmar Ratio Rank: 50
PDN Martin Ratio Rank: 56

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.

VSS vs. PDN - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard FTSE All-World ex-US Small-Cap ETF (VSS) and Invesco FTSE RAFI Developed Markets ex-U.S. Small-Mid ETF (PDN). 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.

	VSS	PDN	Difference
Sharpe ratio: Return per unit of total volatility	1.85	1.91	-0.05
Sortino ratio: Return per unit of downside risk	2.54	2.68	-0.14
Omega ratio: Gain probability vs. loss probability	1.34	1.35	-0.01
Calmar ratio: Return relative to maximum drawdown	2.36	2.47	-0.11
Martin ratio: Return relative to average drawdown	9.13	9.64	-0.51
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VSS vs. PDN - Sharpe Ratio Comparison

The current VSS Sharpe Ratio is 1.85, which is comparable to the PDN Sharpe Ratio of 1.91. The chart below compares the historical Sharpe Ratios of VSS and PDN, 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

	VSS	PDN	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.85	1.91	-0.05
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.35	0.40	-0.04
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.47	0.49	-0.03
Sharpe Ratio (All Time) Calculated using the full available price history	0.55	0.27	+0.27

Drawdowns

VSS vs. PDN - Drawdown Comparison

The maximum VSS drawdown since its inception was -43.51%, smaller than the maximum PDN drawdown of -59.32%. Use the drawdown chart below to compare losses from any high point for VSS and PDN.

Drawdown Indicators

	VSS	PDN	Difference
Max Drawdown Largest peak-to-trough decline	-43.51%	-59.32%	+15.81%
Max Drawdown (1Y) Largest decline over 1 year	-11.62%	-11.26%	-0.36%
Max Drawdown (3Y) Largest decline over 3 years	-15.73%	-13.25%	-2.48%
Max Drawdown (5Y) Largest decline over 5 years	-33.93%	-33.68%	-0.25%
Max Drawdown (10Y) Largest decline over 10 years	-43.51%	-41.94%	-1.57%
Current Drawdown Current decline from peak	-2.58%	-2.62%	+0.04%
Average Drawdown Average peak-to-trough decline	-9.64%	-11.59%	+1.95%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.00%	2.88%	+0.12%

Volatility

VSS vs. PDN - Volatility Comparison

Vanguard FTSE All-World ex-US Small-Cap ETF (VSS) has a higher volatility of 5.33% compared to Invesco FTSE RAFI Developed Markets ex-U.S. Small-Mid ETF (PDN) at 4.74%. This indicates that VSS's price experiences larger fluctuations and is considered to be riskier than PDN based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VSS	PDN	Difference
Volatility (1M) Calculated over the trailing 1-month period	5.33%	4.74%	+0.59%
Volatility (6M) Calculated over the trailing 6-month period	12.64%	12.11%	+0.53%
Volatility (1Y) Calculated over the trailing 1-year period	14.81%	14.61%	+0.20%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.46%	16.34%	+0.12%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	17.27%	17.06%	+0.21%

VSS vs. PDN - Expense Ratio Comparison

VSS has a 0.07% expense ratio, which is lower than PDN's 0.49% expense ratio.

Dividends

VSS vs. PDN - Dividend Comparison

VSS's dividend yield for the trailing twelve months is around 3.07%, which matches PDN's 3.08% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PDN Invesco FTSE RAFI Developed Markets ex-U.S. Small-Mid ETF	3.08%	3.36%	3.36%	3.16%	2.68%	2.42%	1.79%	2.60%	2.21%	2.42%	2.16%	2.06%
VSS Vanguard FTSE All-World ex-US Small-Cap ETF	3.07%	3.39%	3.44%	3.14%	2.30%	2.74%	1.90%	3.25%	2.80%	2.83%	2.93%	2.66%

Frequently Asked Questions

Can I hold both VSS and PDN in my portfolio?

With a correlation of 0.95, VSS and PDN 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, VSS or PDN?

VSS has higher volatility (5.33%) compared to PDN (4.74%). In terms of maximum drawdown, VSS dropped -43.51% vs PDN's -59.32%.

Which ETF is better, VSS or PDN?

On 10-year performance, PDN leads with 8.41% vs 8.07% for VSS. On fees, VSS is cheaper at 0.07% per year. On volatility, PDN has been the lower-risk option at 4.74%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, VSS or PDN?

Over the 10-year period, PDN has performed better with a 8.41% return vs 8.07%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, VSS or PDN?

VSS is cheaper with a 0.07% expense ratio, compared with 0.49% for PDN.

Which ETF pays a higher dividend yield, VSS or PDN?

VSS and PDN have nearly identical dividend yields, around 3.07%.

What is the main difference between VSS and PDN?

VSS tracks FTSE Global Small Cap ex US Index, while PDN tracks FTSE RAFI Developed x US Mid/Small. They also come from different issuers: Vanguard and Invesco. Their fees differ too: 0.07% for VSS and 0.49% for PDN.

Which has better risk-adjusted returns?

PDN currently has the higher Sharpe Ratio (1.91 vs 1.85), 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.