BBMUX vs. PRMDX

Last updated Aug 5, 2026

BBMUX (Bridge Builder Municipal Bond Fund) and PRMDX (T. Rowe Price Maryland Short-Term Tax-Free Bond Fund) are both Municipal Bonds funds. Over the past 10 years, BBMUX returned 1.84%/yr vs 1.57%/yr for PRMDX. Their 0.49 correlation means their historical movements had little consistent relationship. BBMUX charges 0.15%/yr vs 0.53%/yr for PRMDX.

Performance

BBMUX vs. PRMDX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Bridge Builder Municipal Bond Fund (BBMUX) 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, BBMUX achieves a -0.09% return, which is significantly lower than PRMDX's 0.67% return. Over the past 10 years, BBMUX has outperformed PRMDX with an annualized return of 1.84%, while PRMDX has yielded a comparatively lower 1.57% annualized return.

BBMUX

• 1D: 0.10%
• 1M: -1.70%
• 6M: -0.88%
• YTD: -0.09%
• 1Y: 3.87%
• 3Y*: 3.36%
• 5Y*: 0.58%
• 10Y*: 1.84%
• ALL TIME*: 2.03%

PRMDX

• 1D: 0.00%
• 1M: -0.39%
• 6M: 0.26%
• YTD: 0.67%
• 1Y: 1.78%
• 3Y*: 3.92%
• 5Y*: 2.15%
• 10Y*: 1.57%
• ALL TIME*: 2.33%

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

Liquidity Comparison

Position	Avg. Volume Value (2W)	Avg. Volume Value (1M)	Avg. Volume Value (3M)
BBMUX Bridge Builder Municipal Bond Fund	$0.00	$0.00	$0.00
PRMDX T. Rowe Price Maryland Short-Term Tax-Free Bond Fund	$0.00	$0.00	$0.00

BBMUX vs. PRMDX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
BBMUX Bridge Builder Municipal Bond Fund	-0.09%	5.10%	1.50%	5.56%	-8.23%	2.04%	4.01%	7.15%	1.49%	4.75%
PRMDX T. Rowe Price Maryland Short-Term Tax-Free Bond Fund	0.67%	4.24%	3.84%	4.83%	-2.29%	0.30%	1.15%	2.52%	0.98%	1.09%

Correlation

The correlation between BBMUX and PRMDX is 0.37, which is low. Their historical price movements had little consistent relationship.

	Correlation
Correlation (1Y) Focuses on recent behavior, but can change the most.	0.37
Correlation (3Y) Balances recent behavior with more history.	0.50
Correlation (5Y) Shows whether the relationship held over a longer period.	0.54
Correlation (10Y) Provides a long-term view across more market conditions.	0.50
Correlation (All Time) Calculated using the full available price history since Sep 21, 2015	0.49

The correlation between BBMUX and PRMDX shifts across timeframes, from 0.37 (1 year) to 0.54 (5 years), reflecting how their relationship changes across market environments.

Return for Risk

BBMUX vs. PRMDX — Risk / Return Rank

Compare historical risk-adjusted metric ranks over the past 12 months.

BBMUX

BBMUX Risk / Return Rank: 54
BBMUX Sharpe Ratio Rank: 62
BBMUX Sortino Ratio Rank: 70
BBMUX Omega Ratio Rank: 82
BBMUX Calmar Ratio Rank: 28
BBMUX Martin Ratio Rank: 27

PRMDX

PRMDX Risk / Return Rank: 53
PRMDX Sharpe Ratio Rank: 39
PRMDX Sortino Ratio Rank: 54
PRMDX Omega Ratio Rank: 96
PRMDX Calmar Ratio Rank: 41
PRMDX Martin Ratio Rank: 34

The rank (0–100) uses a weighted average of the Sharpe, Sortino, Omega, Calmar, and Martin percentile ranks for the trailing 12 months. Higher means stronger historical risk-adjusted performance within the peer group.

BBMUX vs. PRMDX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Bridge Builder Municipal Bond Fund (BBMUX) 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.

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.

	BBMUX	PRMDX	Difference
Sharpe ratio: Return per unit of total volatility	1.72	1.35	+0.36
Sortino ratio: Return per unit of downside risk	2.59	2.29	+0.30
Omega ratio: Gain probability vs. loss probability	1.40	1.57	-0.17
Calmar ratio: Return relative to maximum drawdown	1.44	1.85	-0.41
Martin ratio: Return relative to average drawdown	4.35	5.53	-1.18

BBMUX vs. PRMDX - Sharpe Ratio Comparison

The current BBMUX Sharpe Ratio is 1.72, which is comparable to the PRMDX Sharpe Ratio of 1.35. The chart below compares the historical Sharpe Ratios of BBMUX 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.

Drawdowns

BBMUX vs. PRMDX - Drawdown Comparison

The maximum BBMUX drawdown since its inception was -12.65%, which is greater than PRMDX's maximum drawdown of -4.31%. Use the drawdown chart below to compare losses from any high point for BBMUX and PRMDX.

Drawdown Indicators

	BBMUX	PRMDX	Difference
Max Drawdown Largest peak-to-trough decline	-12.65%	-4.31%	-8.34%
Max Drawdown (1Y) Largest decline over 1 year	-2.85%	-0.96%	-1.89%
Max Drawdown (3Y) Largest decline over 3 years	-3.96%	-1.56%	-2.40%
Max Drawdown (5Y) Largest decline over 5 years	-12.57%	-4.31%	-8.26%
Max Drawdown (10Y) Largest decline over 10 years	-12.65%	-4.31%	-8.34%
Current Drawdown Current decline from peak	-1.94%	-0.39%	-1.55%
Average Drawdown Average peak-to-trough decline	-2.25%	-0.36%	-1.89%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.93%	0.32%	+0.61%

Volatility

BBMUX vs. PRMDX - Volatility Comparison

Bridge Builder Municipal Bond Fund (BBMUX) has a higher volatility of 0.74% compared to T. Rowe Price Maryland Short-Term Tax-Free Bond Fund (PRMDX) at 0.27%. This indicates that BBMUX's price experiences larger fluctuations and is considered to be riskier than PRMDX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BBMUX	PRMDX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.74%	0.27%	+0.47%
Volatility (6M) Calculated over the trailing 6-month period	1.93%	1.03%	+0.90%
Volatility (1Y) Calculated over the trailing 1-year period	2.40%	1.32%	+1.08%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.26%	1.75%	+1.51%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	3.25%	1.64%	+1.61%

BBMUX vs. PRMDX - Expense Ratio Comparison

BBMUX has a 0.15% expense ratio, which is lower than PRMDX's 0.53% expense ratio.

Dividends

BBMUX vs. PRMDX - Dividend Comparison

BBMUX's dividend yield for the trailing twelve months is around 3.12%, more than PRMDX's 2.35% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BBMUX Bridge Builder Municipal Bond Fund	3.12%	3.61%	2.81%	2.21%	1.82%	1.93%	2.10%	2.61%	2.35%	1.95%	0.35%	0.06%
PRMDX T. Rowe Price Maryland Short-Term Tax-Free Bond Fund	2.35%	3.16%	4.15%	3.10%	0.61%	0.69%	1.14%	1.33%	1.16%	0.89%	0.74%	0.67%

Frequently Asked Questions

Can I hold both BBMUX and PRMDX in my portfolio?

BBMUX and PRMDX have a correlation of 0.37, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, BBMUX or PRMDX?

BBMUX has higher volatility (0.74%) compared to PRMDX (0.27%). In terms of maximum drawdown, BBMUX dropped -12.65% vs PRMDX's -4.31%.

Which has better risk-adjusted returns?

BBMUX currently has the higher Sharpe Ratio (1.72 vs 1.35), 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.