MURNX vs. MARMX

Last updated Jun 5, 2026

MURNX (Mutual of America Investment Corporation - 2050 Retirement Fund) and MARMX (Mutual of America Retirement Income Fund) are both Target Retirement Date funds from Mutual of America. Over the past 5 years, MURNX returned 8.26%/yr vs 3.16%/yr for MARMX. Their correlation of 0.84 suggests significant overlap in exposure. MURNX charges 0.08%/yr vs 0.13%/yr for MARMX.

Performance

MURNX vs. MARMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Mutual of America Investment Corporation - 2050 Retirement Fund (MURNX) and Mutual of America Retirement Income Fund (MARMX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MURNX achieves a 9.23% return, which is significantly higher than MARMX's 3.41% return.

MURNX

• 1D: -0.60%
• 1M: 2.62%
• YTD: 9.23%
• 6M: 9.54%
• 1Y: 23.00%
• 3Y*: 16.45%
• 5Y*: 8.26%
• 10Y*: —

MARMX

• 1D: -0.33%
• 1M: 1.17%
• YTD: 3.41%
• 6M: 3.69%
• 1Y: 10.61%
• 3Y*: 7.88%
• 5Y*: 3.16%
• 10Y*: —

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

MURNX vs. MARMX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020
MURNX Mutual of America Investment Corporation - 2050 Retirement Fund	9.23%	17.89%	14.37%	15.78%	-16.25%	17.85%	1,041.40%
MARMX Mutual of America Retirement Income Fund	3.41%	10.54%	5.88%	7.79%	-11.40%	3.49%	890.98%

Correlation

The correlation between MURNX and MARMX is 0.91, 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	0.91
Correlation (3Y) Calculated over the trailing 3-year period	0.88
Correlation (5Y) Calculated over the trailing 5-year period	0.85
Correlation (All Time) Calculated using the full available price history since Jun 29, 2020	0.84

The correlation between MURNX and MARMX has been stable across timeframes, ranging from 0.84 to 0.91 - a consistent structural relationship.

Return for Risk

MURNX vs. MARMX — Risk / Return Rank

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

MURNX

MURNX Risk / Return Rank: 65
MURNX Sharpe Ratio Rank: 59
MURNX Sortino Ratio Rank: 64
MURNX Omega Ratio Rank: 57
MURNX Calmar Ratio Rank: 66
MURNX Martin Ratio Rank: 79

MARMX

MARMX Risk / Return Rank: 75
MARMX Sharpe Ratio Rank: 73
MARMX Sortino Ratio Rank: 80
MARMX Omega Ratio Rank: 73
MARMX Calmar Ratio Rank: 71
MARMX Martin Ratio Rank: 80

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.

MURNX vs. MARMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Mutual of America Investment Corporation - 2050 Retirement Fund (MURNX) and Mutual of America Retirement Income Fund (MARMX). 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.

	MURNX	MARMX	Difference
Sharpe ratio: Return per unit of total volatility	2.22	2.43	-0.22
Sortino ratio: Return per unit of downside risk	3.27	3.76	-0.49
Omega ratio: Gain probability vs. loss probability	1.41	1.47	-0.06
Calmar ratio: Return relative to maximum drawdown	3.06	3.16	-0.10
Martin ratio: Return relative to average drawdown	14.46	14.44	+0.02
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

MURNX vs. MARMX - Sharpe Ratio Comparison

The current MURNX Sharpe Ratio is 2.22, which is comparable to the MARMX Sharpe Ratio of 2.43. The chart below compares the historical Sharpe Ratios of MURNX and MARMX, 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

	MURNX	MARMX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.22	2.43	-0.22
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.54	0.47	+0.07
Sharpe Ratio (All Time) Calculated using the full available price history	0.17	0.15	+0.02

Drawdowns

MURNX vs. MARMX - Drawdown Comparison

The maximum MURNX drawdown since its inception was -32.96%, which is greater than MARMX's maximum drawdown of -16.21%. Use the drawdown chart below to compare losses from any high point for MURNX and MARMX.

Drawdown Indicators

	MURNX	MARMX	Difference
Max Drawdown Largest peak-to-trough decline	-32.96%	-16.21%	-16.75%
Max Drawdown (1Y) Largest decline over 1 year	-8.50%	-3.92%	-4.58%
Max Drawdown (3Y) Largest decline over 3 years	-15.36%	-5.64%	-9.72%
Max Drawdown (5Y) Largest decline over 5 years	-23.75%	-15.94%	-7.81%
Current Drawdown Current decline from peak	-0.60%	-0.33%	-0.27%
Average Drawdown Average peak-to-trough decline	-5.50%	-4.28%	-1.22%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.72%	0.82%	+0.90%

Volatility

MURNX vs. MARMX - Volatility Comparison

Mutual of America Investment Corporation - 2050 Retirement Fund (MURNX) has a higher volatility of 3.28% compared to Mutual of America Retirement Income Fund (MARMX) at 1.76%. This indicates that MURNX's price experiences larger fluctuations and is considered to be riskier than MARMX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MURNX	MARMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.28%	1.76%	+1.52%
Volatility (6M) Calculated over the trailing 6-month period	9.41%	4.12%	+5.29%
Volatility (1Y) Calculated over the trailing 1-year period	11.71%	5.09%	+6.62%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.23%	7.53%	+9.70%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	381.67%	393.21%	-11.54%

MURNX vs. MARMX - Expense Ratio Comparison

MURNX has a 0.08% expense ratio, which is lower than MARMX's 0.13% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

MURNX vs. MARMX - Dividend Comparison

MURNX's dividend yield for the trailing twelve months is around 8.52%, more than MARMX's 4.18% yield.

Position	TTM	2025	2024	2023	2022	2021
MARMX Mutual of America Retirement Income Fund	4.18%	4.32%	4.16%	1.55%	5.73%	2.03%
MURNX Mutual of America Investment Corporation - 2050 Retirement Fund	8.52%	9.30%	6.49%	3.56%	11.26%	3.72%

Frequently Asked Questions

Can I hold both MURNX and MARMX in my portfolio?

With a correlation of 0.91, MURNX and MARMX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, MURNX or MARMX?

MURNX has higher volatility (3.28%) compared to MARMX (1.76%). In terms of maximum drawdown, MURNX dropped -32.96% vs MARMX's -16.21%.

Which has better risk-adjusted returns?

MARMX currently has the higher Sharpe Ratio (2.43 vs 2.22), 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.