MPSAX vs. MSTDX

Last updated Jun 23, 2026

MPSAX (MassMutual Inflation-Protected and Income Fund) and MSTDX (MassMutual Short Duration Bond Fund) are both mutual funds - MPSAX is a Inflation-Protected Bonds fund managed by MassMutual, while MSTDX is a Short-Term Bond fund managed by MassMutual. Over the past 10 years, MPSAX returned 3.37%/yr vs 2.04%/yr for MSTDX. A 0.54 correlation means they provide meaningful diversification when combined. MPSAX charges 1.02%/yr vs 0.51%/yr for MSTDX.

Performance

MPSAX vs. MSTDX - Performance Comparison

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

Returns By Period

In the year-to-date period, MPSAX achieves a 0.82% return, which is significantly higher than MSTDX's 0.73% return. Over the past 10 years, MPSAX has outperformed MSTDX with an annualized return of 3.37%, while MSTDX has yielded a comparatively lower 2.04% annualized return.

MPSAX

• 1D: 0.11%
• 1M: 0.32%
• YTD: 0.82%
• 6M: 1.21%
• 1Y: 2.77%
• 3Y*: 2.93%
• 5Y*: 2.72%
• 10Y*: 3.37%

MSTDX

• 1D: 0.11%
• 1M: 0.33%
• YTD: 0.73%
• 6M: 1.24%
• 1Y: 4.18%
• 3Y*: 5.66%
• 5Y*: 1.32%
• 10Y*: 2.04%

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

MPSAX vs. MSTDX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MPSAX MassMutual Inflation-Protected and Income Fund	0.82%	5.50%	-0.02%	4.93%	-13.72%	20.31%	10.79%	7.67%	-1.86%	2.86%
MSTDX MassMutual Short Duration Bond Fund	0.73%	6.18%	6.38%	5.88%	-11.19%	1.79%	2.29%	4.49%	1.68%	2.61%

Correlation

The correlation between MPSAX and MSTDX is 0.61, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.61
Correlation (3Y) Calculated over the trailing 3-year period	0.66
Correlation (5Y) Calculated over the trailing 5-year period	0.51
Correlation (10Y) Calculated over the trailing 10-year period	0.44
Correlation (All Time) Calculated using the full available price history since Dec 31, 2003	0.54

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

Return for Risk

MPSAX vs. MSTDX — Risk / Return Rank

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

MPSAX

MPSAX Risk / Return Rank: 13
MPSAX Sharpe Ratio Rank: 11
MPSAX Sortino Ratio Rank: 11
MPSAX Omega Ratio Rank: 10
MPSAX Calmar Ratio Rank: 18
MPSAX Martin Ratio Rank: 13

MSTDX

MSTDX Risk / Return Rank: 88
MSTDX Sharpe Ratio Rank: 77
MSTDX Sortino Ratio Rank: 93
MSTDX Omega Ratio Rank: 90
MSTDX Calmar Ratio Rank: 87
MSTDX Martin Ratio Rank: 91

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.

MPSAX vs. MSTDX - Risk-Adjusted Trends Comparison

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

	MPSAX	MSTDX	Difference
Sharpe ratio: Return per unit of total volatility	0.85	2.35	-1.50
Sortino ratio: Return per unit of downside risk	1.27	4.37	-3.10
Omega ratio: Gain probability vs. loss probability	1.15	1.62	-0.47
Calmar ratio: Return relative to maximum drawdown	1.42	4.05	-2.62
Martin ratio: Return relative to average drawdown	3.38	16.84	-13.46

MPSAX vs. MSTDX - Sharpe Ratio Comparison

The current MPSAX Sharpe Ratio is 0.85, which is lower than the MSTDX Sharpe Ratio of 2.35. The chart below compares the historical Sharpe Ratios of MPSAX and MSTDX, 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

MPSAX vs. MSTDX - Drawdown Comparison

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

Drawdown Indicators

	MPSAX	MSTDX	Difference
Max Drawdown Largest peak-to-trough decline	-19.35%	-13.31%	-6.04%
Max Drawdown (1Y) Largest decline over 1 year	-2.04%	-1.06%	-0.98%
Max Drawdown (3Y) Largest decline over 3 years	-4.01%	-1.06%	-2.95%
Max Drawdown (5Y) Largest decline over 5 years	-19.35%	-13.31%	-6.04%
Max Drawdown (10Y) Largest decline over 10 years	-19.35%	-13.31%	-6.04%
Current Drawdown Current decline from peak	-8.65%	-0.21%	-8.44%
Average Drawdown Average peak-to-trough decline	-6.19%	-1.43%	-4.76%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.86%	0.26%	+0.60%

Volatility

MPSAX vs. MSTDX - Volatility Comparison

MassMutual Inflation-Protected and Income Fund (MPSAX) has a higher volatility of 1.18% compared to MassMutual Short Duration Bond Fund (MSTDX) at 0.63%. This indicates that MPSAX's price experiences larger fluctuations and is considered to be riskier than MSTDX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MPSAX	MSTDX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.18%	0.63%	+0.55%
Volatility (6M) Calculated over the trailing 6-month period	2.44%	1.40%	+1.04%
Volatility (1Y) Calculated over the trailing 1-year period	3.42%	1.83%	+1.59%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	11.76%	2.34%	+9.42%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	8.97%	2.06%	+6.91%

MPSAX vs. MSTDX - Expense Ratio Comparison

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

Dividends

MPSAX vs. MSTDX - Dividend Comparison

MPSAX's dividend yield for the trailing twelve months is around 3.43%, less than MSTDX's 4.44% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MPSAX MassMutual Inflation-Protected and Income Fund	3.43%	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	4.44%	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 MPSAX and MSTDX in my portfolio?

MPSAX and MSTDX have a correlation of 0.61, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, MPSAX or MSTDX?

MPSAX has higher volatility (1.18%) compared to MSTDX (0.63%). In terms of maximum drawdown, MPSAX dropped -19.35% vs MSTDX's -13.31%.

Which has better risk-adjusted returns?

MSTDX currently has the higher Sharpe Ratio (2.35 vs 0.85), 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.