RYSOX vs. MIEYX

Last updated Jun 24, 2026

RYSOX (Rydex S&P 500 Fund) and MIEYX (MM S&P 500 Index Fund) are both S&P 500 funds tracking the S&P 500 Index, from Rydex Funds and MassMutual respectively. Both are passively managed. Over the past 10 years, RYSOX returned 13.84%/yr vs 14.74%/yr for MIEYX. With a 0.99 correlation, they move nearly in lockstep. RYSOX charges 1.56%/yr vs 0.46%/yr for MIEYX.

Performance

RYSOX vs. MIEYX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Rydex S&P 500 Fund (RYSOX) and MM S&P 500 Index Fund (MIEYX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, RYSOX achieves a 8.94% return, which is significantly lower than MIEYX's 9.52% return. Over the past 10 years, RYSOX has underperformed MIEYX with an annualized return of 13.84%, while MIEYX has yielded a comparatively higher 14.74% annualized return.

RYSOX

• 1D: -0.37%
• 1M: -0.02%
• YTD: 8.94%
• 6M: 7.91%
• 1Y: 23.49%
• 3Y*: 19.41%
• 5Y*: 11.75%
• 10Y*: 13.84%

MIEYX

• 1D: -0.39%
• 1M: 0.07%
• YTD: 9.52%
• 6M: 8.51%
• 1Y: 24.87%
• 3Y*: 20.83%
• 5Y*: 13.01%
• 10Y*: 14.74%

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

RYSOX vs. MIEYX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
RYSOX Rydex S&P 500 Fund	8.94%	15.93%	22.98%	24.15%	-19.47%	26.68%	16.25%	29.15%	-6.01%	19.53%
MIEYX MM S&P 500 Index Fund	9.52%	17.27%	24.36%	25.76%	-18.63%	28.02%	17.87%	30.98%	-5.26%	18.90%

Correlation

The correlation between RYSOX and MIEYX is 1.00 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	1.00
Correlation (3Y) Calculated over the trailing 3-year period	0.98
Correlation (5Y) Calculated over the trailing 5-year period	0.99
Correlation (10Y) Calculated over the trailing 10-year period	0.99
Correlation (All Time) Calculated using the full available price history since Jan 3, 2007	0.99

The correlation between RYSOX and MIEYX has been stable across timeframes, ranging from 0.98 to 1.00 - a consistent structural relationship.

Return for Risk

RYSOX vs. MIEYX — Risk / Return Rank

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

RYSOX

RYSOX Risk / Return Rank: 55
RYSOX Sharpe Ratio Rank: 53
RYSOX Sortino Ratio Rank: 49
RYSOX Omega Ratio Rank: 51
RYSOX Calmar Ratio Rank: 55
RYSOX Martin Ratio Rank: 66

MIEYX

MIEYX Risk / Return Rank: 62
MIEYX Sharpe Ratio Rank: 60
MIEYX Sortino Ratio Rank: 54
MIEYX Omega Ratio Rank: 56
MIEYX Calmar Ratio Rank: 64
MIEYX Martin Ratio Rank: 75

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.

RYSOX vs. MIEYX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Rydex S&P 500 Fund (RYSOX) and MM S&P 500 Index Fund (MIEYX). 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.

	RYSOX	MIEYX	Difference
Sharpe ratio: Return per unit of total volatility	1.99	2.10	-0.11
Sortino ratio: Return per unit of downside risk	2.71	2.84	-0.13
Omega ratio: Gain probability vs. loss probability	1.36	1.38	-0.02
Calmar ratio: Return relative to maximum drawdown	2.73	2.94	-0.20
Martin ratio: Return relative to average drawdown	12.10	13.21	-1.11

RYSOX vs. MIEYX - Sharpe Ratio Comparison

The current RYSOX Sharpe Ratio is 1.99, which is comparable to the MIEYX Sharpe Ratio of 2.10. The chart below compares the historical Sharpe Ratios of RYSOX and MIEYX, 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

RYSOX vs. MIEYX - Drawdown Comparison

The maximum RYSOX drawdown since its inception was -55.24%, roughly equal to the maximum MIEYX drawdown of -55.63%. Use the drawdown chart below to compare losses from any high point for RYSOX and MIEYX.

Drawdown Indicators

	RYSOX	MIEYX	Difference
Max Drawdown Largest peak-to-trough decline	-55.24%	-55.63%	+0.39%
Max Drawdown (1Y) Largest decline over 1 year	-9.06%	-8.92%	-0.14%
Max Drawdown (3Y) Largest decline over 3 years	-18.94%	-36.63%	+17.69%
Max Drawdown (5Y) Largest decline over 5 years	-25.45%	-36.63%	+11.18%
Max Drawdown (10Y) Largest decline over 10 years	-34.05%	-36.63%	+2.58%
Current Drawdown Current decline from peak	-1.80%	-4.12%	+2.32%
Average Drawdown Average peak-to-trough decline	-8.25%	-12.55%	+4.30%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.04%	1.98%	+0.06%

Volatility

RYSOX vs. MIEYX - Volatility Comparison

Rydex S&P 500 Fund (RYSOX) and MM S&P 500 Index Fund (MIEYX) have volatilities of 4.67% and 4.69%, 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

	RYSOX	MIEYX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.67%	4.69%	-0.02%
Volatility (6M) Calculated over the trailing 6-month period	9.81%	9.84%	-0.03%
Volatility (1Y) Calculated over the trailing 1-year period	12.48%	12.52%	-0.04%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.00%	25.57%	-8.57%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.14%	22.61%	-4.47%

RYSOX vs. MIEYX - Expense Ratio Comparison

RYSOX has a 1.56% expense ratio, which is higher than MIEYX's 0.46% expense ratio.

Dividends

RYSOX vs. MIEYX - Dividend Comparison

RYSOX's dividend yield for the trailing twelve months is around 2.43%, less than MIEYX's 16.10% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
MIEYX MM S&P 500 Index Fund	16.10%	17.63%	32.89%	7.13%	33.24%	13.29%	16.29%	6.38%	19.14%	21.81%	4.19%	2.29%
RYSOX Rydex S&P 500 Fund	2.43%	2.65%	1.08%	0.60%	1.17%	1.25%	13.42%	0.93%	1.69%	4.56%	0.84%	4.01%

Frequently Asked Questions

Can I hold both RYSOX and MIEYX in my portfolio?

With a correlation of 1.00, RYSOX and MIEYX 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, RYSOX or MIEYX?

MIEYX has higher volatility (4.69%) compared to RYSOX (4.67%). In terms of maximum drawdown, RYSOX dropped -55.24% vs MIEYX's -55.63%.

Which has better risk-adjusted returns?

MIEYX currently has the higher Sharpe Ratio (2.10 vs 1.99), 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.