GSY vs. VMMSX

Last updated Jun 23, 2026

GSY (Invesco Ultra Short Duration ETF) and VMMSX (Vanguard Emerging Markets Select Stock Fund) are both funds - GSY is a Ultrashort Bond fund actively managed by Invesco, while VMMSX is a Emerging Markets Equities fund managed by Vanguard. Over the past 10 years, GSY returned 2.86%/yr vs 10.41%/yr for VMMSX. At a 0.07 correlation, their price movements are largely independent. GSY charges 0.22%/yr vs 0.84%/yr for VMMSX.

Performance

GSY vs. VMMSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Invesco Ultra Short Duration ETF (GSY) and Vanguard Emerging Markets Select Stock Fund (VMMSX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, GSY achieves a 1.79% return, which is significantly lower than VMMSX's 17.85% return. Over the past 10 years, GSY has underperformed VMMSX with an annualized return of 2.86%, while VMMSX has yielded a comparatively higher 10.41% annualized return.

GSY

• 1D: 0.03%
• 1M: 0.35%
• YTD: 1.79%
• 6M: 1.87%
• 1Y: 4.45%
• 3Y*: 5.42%
• 5Y*: 3.69%
• 10Y*: 2.86%

VMMSX

• 1D: 1.41%
• 1M: 2.22%
• YTD: 17.85%
• 6M: 19.34%
• 1Y: 43.08%
• 3Y*: 19.12%
• 5Y*: 6.83%
• 10Y*: 10.41%

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

GSY vs. VMMSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
GSY Invesco Ultra Short Duration ETF	1.79%	4.96%	5.95%	5.99%	0.01%	0.03%	1.88%	3.39%	2.18%	1.86%
VMMSX Vanguard Emerging Markets Select Stock Fund	17.85%	35.68%	5.91%	10.58%	-18.15%	-1.40%	15.79%	21.42%	-12.53%	32.01%

Correlation

The correlation between GSY and VMMSX is 0.18, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.18
Correlation (3Y) Calculated over the trailing 3-year period	0.15
Correlation (5Y) Calculated over the trailing 5-year period	0.13
Correlation (10Y) Calculated over the trailing 10-year period	0.08
Correlation (All Time) Calculated using the full available price history since Jun 27, 2011	0.07

The correlation between GSY and VMMSX shifts across timeframes, from 0.07 (all time) to 0.18 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

GSY vs. VMMSX — Risk / Return Rank

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

GSY

GSY Risk / Return Rank: 99
GSY Sharpe Ratio Rank: 99
GSY Sortino Ratio Rank: 99
GSY Omega Ratio Rank: 99
GSY Calmar Ratio Rank: 100
GSY Martin Ratio Rank: 100

VMMSX

VMMSX Risk / Return Rank: 70
VMMSX Sharpe Ratio Rank: 78
VMMSX Sortino Ratio Rank: 63
VMMSX Omega Ratio Rank: 75
VMMSX Calmar Ratio Rank: 73
VMMSX Martin Ratio Rank: 65

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.

GSY vs. VMMSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Invesco Ultra Short Duration ETF (GSY) and Vanguard Emerging Markets Select Stock Fund (VMMSX). 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.

	GSY	VMMSX	Difference
Sharpe ratio: Return per unit of total volatility	10.83	2.36	+8.46
Sortino ratio: Return per unit of downside risk	25.27	3.02	+22.25
Omega ratio: Gain probability vs. loss probability	6.07	1.44	+4.63
Calmar ratio: Return relative to maximum drawdown	74.56	3.14	+71.42
Martin ratio: Return relative to average drawdown	349.93	11.95	+337.98

GSY vs. VMMSX - Sharpe Ratio Comparison

The current GSY Sharpe Ratio is 10.83, which is higher than the VMMSX Sharpe Ratio of 2.36. The chart below compares the historical Sharpe Ratios of GSY and VMMSX, 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

GSY vs. VMMSX - Drawdown Comparison

The maximum GSY drawdown since its inception was -12.14%, smaller than the maximum VMMSX drawdown of -39.28%. Use the drawdown chart below to compare losses from any high point for GSY and VMMSX.

Drawdown Indicators

	GSY	VMMSX	Difference
Max Drawdown Largest peak-to-trough decline	-12.14%	-39.28%	+27.14%
Max Drawdown (1Y) Largest decline over 1 year	-0.06%	-13.46%	+13.40%
Max Drawdown (3Y) Largest decline over 3 years	-0.18%	-18.37%	+18.19%
Max Drawdown (5Y) Largest decline over 5 years	-1.48%	-36.84%	+35.36%
Max Drawdown (10Y) Largest decline over 10 years	-5.25%	-38.82%	+33.57%
Current Drawdown Current decline from peak	0.00%	-2.56%	+2.56%
Average Drawdown Average peak-to-trough decline	-2.38%	-13.37%	+10.99%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.01%	3.53%	-3.52%

Volatility

GSY vs. VMMSX - Volatility Comparison

The current volatility for Invesco Ultra Short Duration ETF (GSY) is 0.15%, while Vanguard Emerging Markets Select Stock Fund (VMMSX) has a volatility of 7.81%. This indicates that GSY experiences smaller price fluctuations and is considered to be less risky than VMMSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	GSY	VMMSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.15%	7.81%	-7.66%
Volatility (6M) Calculated over the trailing 6-month period	0.31%	15.48%	-15.17%
Volatility (1Y) Calculated over the trailing 1-year period	0.41%	17.87%	-17.46%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	0.58%	18.01%	-17.43%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	1.22%	18.47%	-17.25%

GSY vs. VMMSX - Expense Ratio Comparison

GSY has a 0.22% expense ratio, which is lower than VMMSX's 0.84% expense ratio.

Dividends

GSY vs. VMMSX - Dividend Comparison

GSY's dividend yield for the trailing twelve months is around 4.70%, more than VMMSX's 1.97% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
GSY Invesco Ultra Short Duration ETF	4.70%	4.56%	5.31%	4.95%	1.70%	0.58%	1.45%	2.71%	2.30%	1.80%	1.21%	1.17%
VMMSX Vanguard Emerging Markets Select Stock Fund	1.97%	2.32%	3.33%	3.05%	3.71%	6.80%	1.04%	2.04%	2.53%	1.54%	1.44%	1.87%

Frequently Asked Questions

Can I hold both GSY and VMMSX in my portfolio?

GSY and VMMSX have a correlation of 0.18, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, GSY or VMMSX?

VMMSX has higher volatility (7.81%) compared to GSY (0.15%). In terms of maximum drawdown, GSY dropped -12.14% vs VMMSX's -39.28%.

Which has better risk-adjusted returns?

GSY currently has the higher Sharpe Ratio (10.83 vs 2.36), 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.