VSDM vs. PRMDX

Last updated Jun 4, 2026

VSDM (Vanguard Short Duration Tax-Exempt Bond ETF) and PRMDX (T. Rowe Price Maryland Short-Term Tax-Free Bond Fund) are both Municipal Bonds funds. Over the past year, VSDM returned 4.98% vs 4.09% for PRMDX. At a 0.42 correlation, their price movements are largely independent. VSDM charges 0.12%/yr vs 0.53%/yr for PRMDX.

Performance

VSDM vs. PRMDX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Short Duration Tax-Exempt Bond ETF (VSDM) and T. Rowe Price Maryland Short-Term Tax-Free Bond Fund (PRMDX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VSDM achieves a 1.22% return, which is significantly higher than PRMDX's 0.85% return.

VSDM

• 1D: 0.00%
• 1M: 0.47%
• YTD: 1.22%
• 6M: 1.63%
• 1Y: 4.98%
• 3Y*: —
• 5Y*: —
• 10Y*: —

PRMDX

• 1D: 0.00%
• 1M: 0.21%
• YTD: 0.85%
• 6M: 1.51%
• 1Y: 4.09%
• 3Y*: 3.59%
• 5Y*: 1.82%
• 10Y*: 1.43%

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

VSDM vs. PRMDX - Yearly Performance Comparison

	2026 (YTD)	2025	2024
VSDM Vanguard Short Duration Tax-Exempt Bond ETF	1.22%	5.39%	-0.15%
PRMDX T. Rowe Price Maryland Short-Term Tax-Free Bond Fund	0.85%	4.51%	0.24%

Correlation

The correlation between VSDM and PRMDX is 0.30, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.30
Correlation (All Time) Calculated using the full available price history since Nov 22, 2024	0.42

The correlation between VSDM and PRMDX shifts across timeframes, from 0.30 (1 year) to 0.42 (all time), reflecting how their relationship changes across market environments.

Return for Risk

VSDM vs. PRMDX — Risk / Return Rank

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

VSDM

VSDM Risk / Return Rank: 84
VSDM Sharpe Ratio Rank: 94
VSDM Sortino Ratio Rank: 95
VSDM Omega Ratio Rank: 97
VSDM Calmar Ratio Rank: 68
VSDM Martin Ratio Rank: 65

PRMDX

PRMDX Risk / Return Rank: 89
PRMDX Sharpe Ratio Rank: 86
PRMDX Sortino Ratio Rank: 96
PRMDX Omega Ratio Rank: 98
PRMDX Calmar Ratio Rank: 87
PRMDX Martin Ratio Rank: 77

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.

VSDM vs. PRMDX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Short Duration Tax-Exempt Bond ETF (VSDM) and T. Rowe Price Maryland Short-Term Tax-Free Bond Fund (PRMDX). 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.

	VSDM	PRMDX	Difference
Sharpe ratio: Return per unit of total volatility	3.67	2.80	+0.87
Sortino ratio: Return per unit of downside risk	5.35	5.37	-0.03
Omega ratio: Gain probability vs. loss probability	1.92	2.38	-0.47
Calmar ratio: Return relative to maximum drawdown	3.42	4.27	-0.85
Martin ratio: Return relative to average drawdown	12.07	14.49	-2.42
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VSDM vs. PRMDX - Sharpe Ratio Comparison

The current VSDM Sharpe Ratio is 3.67, which is higher than the PRMDX Sharpe Ratio of 2.80. The chart below compares the historical Sharpe Ratios of VSDM and PRMDX, 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

	VSDM	PRMDX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	3.67	2.80	+0.87
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	—	1.06	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.88	—
Sharpe Ratio (All Time) Calculated using the full available price history	2.19	1.44	+0.75

Drawdowns

VSDM vs. PRMDX - Drawdown Comparison

The maximum VSDM drawdown since its inception was -1.81%, smaller than the maximum PRMDX drawdown of -4.31%. Use the drawdown chart below to compare losses from any high point for VSDM and PRMDX.

Drawdown Indicators

	VSDM	PRMDX	Difference
Max Drawdown Largest peak-to-trough decline	-1.81%	-4.31%	+2.50%
Max Drawdown (1Y) Largest decline over 1 year	-1.46%	-0.96%	-0.50%
Max Drawdown (3Y) Largest decline over 3 years	—	-1.56%	—
Max Drawdown (5Y) Largest decline over 5 years	—	-4.31%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-4.31%	—
Current Drawdown Current decline from peak	-0.33%	-0.14%	-0.19%
Average Drawdown Average peak-to-trough decline	-0.32%	-0.37%	+0.05%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.41%	0.28%	+0.13%

Volatility

VSDM vs. PRMDX - Volatility Comparison

The current volatility for Vanguard Short Duration Tax-Exempt Bond ETF (VSDM) is 0.44%, while T. Rowe Price Maryland Short-Term Tax-Free Bond Fund (PRMDX) has a volatility of 0.53%. This indicates that VSDM experiences smaller price fluctuations and is considered to be less risky than PRMDX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VSDM	PRMDX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.44%	0.53%	-0.09%
Volatility (6M) Calculated over the trailing 6-month period	1.07%	1.11%	-0.04%
Volatility (1Y) Calculated over the trailing 1-year period	1.36%	1.47%	-0.11%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	1.95%	1.72%	+0.23%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	1.95%	1.62%	+0.33%

VSDM vs. PRMDX - Expense Ratio Comparison

VSDM has a 0.12% expense ratio, which is lower than PRMDX's 0.53% expense ratio.

Dividends

VSDM vs. PRMDX - Dividend Comparison

VSDM's dividend yield for the trailing twelve months is around 3.11%, less than PRMDX's 3.43% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PRMDX T. Rowe Price Maryland Short-Term Tax-Free Bond Fund	3.43%	3.43%	3.00%	1.93%	0.61%	0.69%	1.14%	1.33%	1.16%	0.89%	0.74%	0.67%
VSDM Vanguard Short Duration Tax-Exempt Bond ETF	3.11%	3.06%	0.35%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both VSDM and PRMDX in my portfolio?

VSDM and PRMDX have a correlation of 0.30, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, VSDM or PRMDX?

PRMDX has higher volatility (0.53%) compared to VSDM (0.44%). In terms of maximum drawdown, VSDM dropped -1.81% vs PRMDX's -4.31%.

Which has better risk-adjusted returns?

VSDM currently has the higher Sharpe Ratio (3.67 vs 2.80), 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.