MFPAX vs. LSMSX

Last updated Jun 6, 2026

MFPAX (MFS Pennsylvania Municipal Bond Fund) and LSMSX (Western Asset SMASh Series TF Fund) are both Municipal Bonds funds. Over the past 5 years, MFPAX returned 0.70%/yr vs 1.17%/yr for LSMSX. Their correlation of 0.83 suggests significant overlap in exposure. MFPAX charges 0.69%/yr vs 0.01%/yr for LSMSX.

Performance

MFPAX vs. LSMSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS Pennsylvania Municipal Bond Fund (MFPAX) and Western Asset SMASh Series TF Fund (LSMSX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MFPAX achieves a 1.99% return, which is significantly lower than LSMSX's 2.18% return.

MFPAX

• 1D: 0.10%
• 1M: 0.72%
• YTD: 1.99%
• 6M: 2.40%
• 1Y: 7.81%
• 3Y*: 4.13%
• 5Y*: 0.70%
• 10Y*: 2.19%

LSMSX

• 1D: 0.00%
• 1M: 0.76%
• YTD: 2.18%
• 6M: 2.48%
• 1Y: 8.19%
• 3Y*: 4.03%
• 5Y*: 1.17%
• 10Y*: —

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

MFPAX vs. LSMSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MFPAX MFS Pennsylvania Municipal Bond Fund	1.99%	4.65%	2.83%	4.90%	-10.76%	2.64%	4.54%	7.69%	1.44%	4.82%
LSMSX Western Asset SMASh Series TF Fund	2.18%	3.22%	2.22%	7.96%	-10.03%	4.11%	4.48%	8.16%	0.46%	4.92%

Correlation

The correlation between MFPAX and LSMSX is 0.81, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.81
Correlation (3Y) Calculated over the trailing 3-year period	0.88
Correlation (5Y) Calculated over the trailing 5-year period	0.89
Correlation (All Time) Calculated using the full available price history since Feb 2, 2017	0.83

The correlation between MFPAX and LSMSX has been stable across timeframes, ranging from 0.81 to 0.89 - a consistent structural relationship.

Return for Risk

MFPAX vs. LSMSX — Risk / Return Rank

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

MFPAX

MFPAX Risk / Return Rank: 71
MFPAX Sharpe Ratio Rank: 80
MFPAX Sortino Ratio Rank: 87
MFPAX Omega Ratio Rank: 90
MFPAX Calmar Ratio Rank: 51
MFPAX Martin Ratio Rank: 46

LSMSX

LSMSX Risk / Return Rank: 77
LSMSX Sharpe Ratio Rank: 89
LSMSX Sortino Ratio Rank: 91
LSMSX Omega Ratio Rank: 93
LSMSX Calmar Ratio Rank: 61
LSMSX Martin Ratio Rank: 49

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.

MFPAX vs. LSMSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS Pennsylvania Municipal Bond Fund (MFPAX) and Western Asset SMASh Series TF Fund (LSMSX). 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.

	MFPAX	LSMSX	Difference
Sharpe ratio: Return per unit of total volatility	2.56	2.89	-0.33
Sortino ratio: Return per unit of downside risk	4.07	4.50	-0.43
Omega ratio: Gain probability vs. loss probability	1.64	1.71	-0.07
Calmar ratio: Return relative to maximum drawdown	2.63	2.91	-0.29
Martin ratio: Return relative to average drawdown	9.46	9.80	-0.34
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MFPAX vs. LSMSX - Sharpe Ratio Comparison

The current MFPAX Sharpe Ratio is 2.56, which is comparable to the LSMSX Sharpe Ratio of 2.89. The chart below compares the historical Sharpe Ratios of MFPAX and LSMSX, 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

	MFPAX	LSMSX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.56	2.89	-0.33
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.16	0.26	-0.10
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.53	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	1.12	0.63	+0.49

Drawdowns

MFPAX vs. LSMSX - Drawdown Comparison

The maximum MFPAX drawdown since its inception was -16.26%, which is greater than LSMSX's maximum drawdown of -15.00%. Use the drawdown chart below to compare losses from any high point for MFPAX and LSMSX.

Drawdown Indicators

	MFPAX	LSMSX	Difference
Max Drawdown Largest peak-to-trough decline	-16.26%	-15.00%	-1.26%
Max Drawdown (1Y) Largest decline over 1 year	-2.99%	-2.82%	-0.17%
Max Drawdown (3Y) Largest decline over 3 years	-7.17%	-7.49%	+0.32%
Max Drawdown (5Y) Largest decline over 5 years	-16.26%	-15.00%	-1.26%
Max Drawdown (10Y) Largest decline over 10 years	-16.26%	—	—
Current Drawdown Current decline from peak	-0.04%	-0.23%	+0.19%
Average Drawdown Average peak-to-trough decline	-2.19%	-2.85%	+0.66%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.83%	0.84%	-0.01%

Volatility

MFPAX vs. LSMSX - Volatility Comparison

MFS Pennsylvania Municipal Bond Fund (MFPAX) and Western Asset SMASh Series TF Fund (LSMSX) have volatilities of 1.22% and 1.19%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MFPAX	LSMSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.22%	1.19%	+0.03%
Volatility (6M) Calculated over the trailing 6-month period	2.28%	2.06%	+0.22%
Volatility (1Y) Calculated over the trailing 1-year period	3.07%	2.86%	+0.21%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	4.28%	4.48%	-0.20%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.13%	4.51%	-0.38%

MFPAX vs. LSMSX - Expense Ratio Comparison

MFPAX has a 0.69% expense ratio, which is higher than LSMSX's 0.01% expense ratio.

Dividends

MFPAX vs. LSMSX - Dividend Comparison

MFPAX's dividend yield for the trailing twelve months is around 3.44%, less than LSMSX's 3.86% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
LSMSX Western Asset SMASh Series TF Fund	3.86%	3.83%	4.30%	3.37%	2.38%	2.73%	2.33%	2.55%	2.34%	0.90%	0.00%	0.00%
MFPAX MFS Pennsylvania Municipal Bond Fund	3.44%	4.47%	3.00%	2.63%	1.92%	2.04%	2.68%	3.48%	3.60%	3.65%	3.63%	3.72%

Frequently Asked Questions

Can I hold both MFPAX and LSMSX in my portfolio?

MFPAX and LSMSX have a correlation of 0.81, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, MFPAX or LSMSX?

MFPAX has higher volatility (1.22%) compared to LSMSX (1.19%). In terms of maximum drawdown, MFPAX dropped -16.26% vs LSMSX's -15.00%.

Which has better risk-adjusted returns?

LSMSX currently has the higher Sharpe Ratio (2.88 vs 2.56), 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.