MSTDX vs. MPSAX

Last updated Aug 1, 2026

MSTDX (MassMutual Short Duration Bond Fund) and MPSAX (MassMutual Inflation-Protected and Income Fund) are both mutual funds - MSTDX is a Short-Term Bond fund managed by MassMutual, while MPSAX is a Inflation-Protected Bonds fund managed by MassMutual. Over the past 10 years, MSTDX returned 2.02%/yr vs 3.13%/yr for MPSAX. Their 0.54 correlation means they have sometimes moved together and sometimes differently. MSTDX charges 0.51%/yr vs 1.02%/yr for MPSAX.

Performance

MSTDX vs. MPSAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MassMutual Short Duration Bond Fund (MSTDX) and MassMutual Inflation-Protected and Income Fund (MPSAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MSTDX achieves a 1.00% return, which is significantly higher than MPSAX's 0.05% return. Over the past 10 years, MSTDX has underperformed MPSAX with an annualized return of 2.02%, while MPSAX has yielded a comparatively higher 3.13% annualized return.

MSTDX

• 1D: 0.11%
• 1M: -0.21%
• 6M: 0.43%
• YTD: 1.00%
• 1Y: 3.14%
• 3Y*: 5.47%
• 5Y*: 1.33%
• 10Y*: 2.02%
• ALL TIME*: 3.25%

MPSAX

• 1D: 0.00%
• 1M: -0.77%
• 6M: -0.39%
• YTD: 0.05%
• 1Y: 0.29%
• 3Y*: 2.59%
• 5Y*: 1.88%
• 10Y*: 3.13%
• ALL TIME*: 3.32%

*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)
MPSAX MassMutual Inflation-Protected and Income Fund	$0.00	$0.00	$0.00
MSTDX MassMutual Short Duration Bond Fund	$0.00	$0.00	$0.00

MSTDX vs. MPSAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MSTDX MassMutual Short Duration Bond Fund	1.00%	6.18%	6.38%	5.88%	-11.19%	1.79%	2.29%	4.49%	1.68%	2.61%
MPSAX MassMutual Inflation-Protected and Income Fund	0.05%	5.50%	-0.02%	4.93%	-13.72%	20.31%	10.79%	7.67%	-1.86%	2.86%

Correlation

The correlation between MSTDX and MPSAX is 0.59, which is moderate. They have sometimes moved together and sometimes differently, sharing some price drivers without tracking each other closely.

	Correlation
Correlation (1Y) Focuses on recent behavior, but can change the most.	0.59
Correlation (3Y) Balances recent behavior with more history.	0.66
Correlation (5Y) Shows whether the relationship held over a longer period.	0.51
Correlation (10Y) Provides a long-term view across more market conditions.	0.44
Correlation (All Time) Calculated using the full available price history since Dec 31, 2003	0.54

The correlation between MSTDX and MPSAX shifts across timeframes, from 0.44 (10 years) to 0.66 (3 years), reflecting how their relationship changes across market environments.

Return for Risk

MSTDX vs. MPSAX — Risk / Return Rank

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

MSTDX

MSTDX Risk / Return Rank: 91
MSTDX Sharpe Ratio Rank: 85
MSTDX Sortino Ratio Rank: 94
MSTDX Omega Ratio Rank: 92
MSTDX Calmar Ratio Rank: 92
MSTDX Martin Ratio Rank: 94

MPSAX

MPSAX Risk / Return Rank: 8
MPSAX Sharpe Ratio Rank: 8
MPSAX Sortino Ratio Rank: 7
MPSAX Omega Ratio Rank: 7
MPSAX Calmar Ratio Rank: 10
MPSAX Martin Ratio Rank: 9

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.

MSTDX vs. MPSAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MassMutual Short Duration Bond Fund (MSTDX) and MassMutual Inflation-Protected and Income Fund (MPSAX). 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.

	MSTDX	MPSAX	Difference
Sharpe ratio: Return per unit of total volatility	2.09	0.31	+1.78
Sortino ratio: Return per unit of downside risk	3.86	0.47	+3.39
Omega ratio: Gain probability vs. loss probability	1.53	1.05	+0.48
Calmar ratio: Return relative to maximum drawdown	3.63	0.50	+3.13
Martin ratio: Return relative to average drawdown	14.61	1.08	+13.53

MSTDX vs. MPSAX - Sharpe Ratio Comparison

The current MSTDX Sharpe Ratio is 2.09, which is higher than the MPSAX Sharpe Ratio of 0.31. The chart below compares the historical Sharpe Ratios of MSTDX and MPSAX, 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

MSTDX vs. MPSAX - Drawdown Comparison

The maximum MSTDX drawdown since its inception was -13.31%, smaller than the maximum MPSAX drawdown of -19.35%. Use the drawdown chart below to compare losses from any high point for MSTDX and MPSAX.

Drawdown Indicators

	MSTDX	MPSAX	Difference
Max Drawdown Largest peak-to-trough decline	-13.31%	-19.35%	+6.04%
Max Drawdown (1Y) Largest decline over 1 year	-1.06%	-2.04%	+0.98%
Max Drawdown (3Y) Largest decline over 3 years	-1.06%	-3.94%	+2.88%
Max Drawdown (5Y) Largest decline over 5 years	-13.31%	-19.35%	+6.04%
Max Drawdown (10Y) Largest decline over 10 years	-13.31%	-19.35%	+6.04%
Current Drawdown Current decline from peak	-0.21%	-9.34%	+9.13%
Average Drawdown Average peak-to-trough decline	-1.42%	-6.21%	+4.79%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.26%	0.94%	-0.68%

Volatility

MSTDX vs. MPSAX - Volatility Comparison

The current volatility for MassMutual Short Duration Bond Fund (MSTDX) is 0.43%, while MassMutual Inflation-Protected and Income Fund (MPSAX) has a volatility of 0.70%. This indicates that MSTDX experiences smaller price fluctuations and is considered to be less risky than MPSAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MSTDX	MPSAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.43%	0.70%	-0.27%
Volatility (6M) Calculated over the trailing 6-month period	1.41%	2.48%	-1.07%
Volatility (1Y) Calculated over the trailing 1-year period	1.85%	3.35%	-1.50%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	2.35%	11.76%	-9.41%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.07%	8.97%	-6.90%

MSTDX vs. MPSAX - Expense Ratio Comparison

MSTDX has a 0.51% expense ratio, which is lower than MPSAX's 1.02% expense ratio.

Dividends

MSTDX vs. MPSAX - Dividend Comparison

MSTDX's dividend yield for the trailing twelve months is around 4.09%, more than MPSAX's 3.30% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MPSAX MassMutual Inflation-Protected and Income Fund	3.30%	3.51%	1.44%	2.47%	3.34%	18.54%	5.13%	1.59%	2.68%	2.34%	2.23%	0.61%
MSTDX MassMutual Short Duration Bond Fund	4.09%	4.36%	2.63%	2.48%	1.46%	1.90%	4.44%	3.35%	3.82%	2.51%	2.36%	2.57%

Frequently Asked Questions

Can I hold both MSTDX and MPSAX in my portfolio?

MSTDX and MPSAX have a correlation of 0.59, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, MSTDX or MPSAX?

MPSAX has higher volatility (0.70%) compared to MSTDX (0.43%). In terms of maximum drawdown, MSTDX dropped -13.31% vs MPSAX's -19.35%.

Which has better risk-adjusted returns?

MSTDX currently has the higher Sharpe Ratio (2.09 vs 0.31), 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.