IIRSX vs. VYMSX

Last updated Jul 14, 2026

IIRSX (Voya Russell Small Cap Index Portfolio) and VYMSX (Voya Mid Cap Research Enhanced Index Fund) are both mutual funds - IIRSX is a Small Cap Blend Equities fund managed by Voya, while VYMSX is a Mid Cap Blend Equities fund managed by Voya. Over the past 10 years, IIRSX returned 10.69%/yr vs 10.32%/yr for VYMSX. A 0.76 correlation means they provide meaningful diversification when combined. IIRSX charges 0.45%/yr vs 0.82%/yr for VYMSX.

Performance

IIRSX vs. VYMSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Voya Russell Small Cap Index Portfolio (IIRSX) and Voya Mid Cap Research Enhanced Index Fund (VYMSX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, IIRSX achieves a 22.00% return, which is significantly higher than VYMSX's 17.27% return. Both investments have delivered pretty close results over the past 10 years, with IIRSX having a 10.69% annualized return and VYMSX not far behind at 10.32%.

IIRSX

• 1D: -0.48%
• 1M: 1.32%
• 6M: 14.85%
• YTD: 22.00%
• 1Y: 34.55%
• 3Y*: 17.73%
• 5Y*: 6.95%
• 10Y*: 10.69%

VYMSX

• 1D: -0.21%
• 1M: 0.91%
• 6M: 12.43%
• YTD: 17.27%
• 1Y: 21.58%
• 3Y*: 14.99%
• 5Y*: 8.93%
• 10Y*: 10.32%

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

IIRSX vs. VYMSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
IIRSX Voya Russell Small Cap Index Portfolio	22.00%	12.84%	11.14%	16.61%	-20.58%	14.32%	19.15%	24.63%	-11.26%	14.32%
VYMSX Voya Mid Cap Research Enhanced Index Fund	17.27%	6.79%	14.92%	17.35%	-14.63%	27.47%	8.26%	28.18%	-14.55%	13.43%

Correlation

The correlation between IIRSX and VYMSX is 0.93, 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	0.93
Correlation (3Y) Calculated over the trailing 3-year period	0.92
Correlation (5Y) Calculated over the trailing 5-year period	0.93
Correlation (10Y) Calculated over the trailing 10-year period	0.94
Correlation (All Time) Calculated using the full available price history since Apr 29, 2002	0.76

The correlation between IIRSX and VYMSX shifts across timeframes, from 0.76 (all time) to 0.94 (10 years), reflecting how their relationship changes across market environments.

Return for Risk

IIRSX vs. VYMSX — Risk / Return Rank

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

IIRSX

IIRSX Risk / Return Rank: 69
IIRSX Sharpe Ratio Rank: 59
IIRSX Sortino Ratio Rank: 59
IIRSX Omega Ratio Rank: 57
IIRSX Calmar Ratio Rank: 88
IIRSX Martin Ratio Rank: 84

VYMSX

VYMSX Risk / Return Rank: 44
VYMSX Sharpe Ratio Rank: 36
VYMSX Sortino Ratio Rank: 38
VYMSX Omega Ratio Rank: 31
VYMSX Calmar Ratio Rank: 56
VYMSX Martin Ratio Rank: 56

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.

IIRSX vs. VYMSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Voya Russell Small Cap Index Portfolio (IIRSX) and Voya Mid Cap Research Enhanced Index Fund (VYMSX). 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.

	IIRSX	VYMSX	Difference
Sharpe ratio: Return per unit of total volatility	1.71	1.33	+0.38
Sortino ratio: Return per unit of downside risk	2.42	1.97	+0.44
Omega ratio: Gain probability vs. loss probability	1.31	1.23	+0.09
Calmar ratio: Return relative to maximum drawdown	3.47	2.31	+1.16
Martin ratio: Return relative to average drawdown	11.94	8.85	+3.09

IIRSX vs. VYMSX - Sharpe Ratio Comparison

The current IIRSX Sharpe Ratio is 1.71, which is comparable to the VYMSX Sharpe Ratio of 1.33. The chart below compares the historical Sharpe Ratios of IIRSX and VYMSX, 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

IIRSX vs. VYMSX - Drawdown Comparison

The maximum IIRSX drawdown since its inception was -63.18%, which is greater than VYMSX's maximum drawdown of -57.85%. Use the drawdown chart below to compare losses from any high point for IIRSX and VYMSX.

Drawdown Indicators

	IIRSX	VYMSX	Difference
Max Drawdown Largest peak-to-trough decline	-63.18%	-57.85%	-5.33%
Max Drawdown (1Y) Largest decline over 1 year	-11.08%	-10.34%	-0.74%
Max Drawdown (3Y) Largest decline over 3 years	-27.95%	-24.02%	-3.93%
Max Drawdown (5Y) Largest decline over 5 years	-32.01%	-31.71%	-0.30%
Max Drawdown (10Y) Largest decline over 10 years	-42.32%	-43.69%	+1.37%
Current Drawdown Current decline from peak	-1.49%	-2.99%	+1.50%
Average Drawdown Average peak-to-trough decline	-11.39%	-9.13%	-2.26%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.09%	2.59%	+0.50%

Volatility

IIRSX vs. VYMSX - Volatility Comparison

The current volatility for Voya Russell Small Cap Index Portfolio (IIRSX) is 4.89%, while Voya Mid Cap Research Enhanced Index Fund (VYMSX) has a volatility of 5.94%. This indicates that IIRSX experiences smaller price fluctuations and is considered to be less risky than VYMSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	IIRSX	VYMSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.89%	5.94%	-1.05%
Volatility (6M) Calculated over the trailing 6-month period	17.81%	13.41%	+4.40%
Volatility (1Y) Calculated over the trailing 1-year period	22.44%	17.89%	+4.55%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	23.65%	23.41%	+0.24%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.92%	22.89%	+1.03%

IIRSX vs. VYMSX - Expense Ratio Comparison

IIRSX has a 0.45% expense ratio, which is lower than VYMSX's 0.82% expense ratio.

Dividends

IIRSX vs. VYMSX - Dividend Comparison

IIRSX's dividend yield for the trailing twelve months is around 13.93%, less than VYMSX's 25.38% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
IIRSX Voya Russell Small Cap Index Portfolio	13.93%	12.31%	7.55%	5.71%	11.02%	0.61%	6.29%	12.33%	8.34%	7.95%	12.75%	11.26%
VYMSX Voya Mid Cap Research Enhanced Index Fund	25.38%	29.77%	11.50%	0.96%	6.78%	14.81%	0.79%	2.00%	13.24%	7.58%	1.83%	6.83%

Frequently Asked Questions

Can I hold both IIRSX and VYMSX in my portfolio?

With a correlation of 0.93, IIRSX and VYMSX 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, IIRSX or VYMSX?

VYMSX has higher volatility (5.94%) compared to IIRSX (4.89%). In terms of maximum drawdown, IIRSX dropped -63.18% vs VYMSX's -57.85%.

Which has better risk-adjusted returns?

IIRSX currently has the higher Sharpe Ratio (1.71 vs 1.33), 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.