OEF vs. IWM

Last updated Jun 4, 2026

OEF (iShares S&P 100 ETF) and IWM (iShares Russell 2000 ETF) are both exchange-traded funds - OEF is a Large Cap Blend Equities fund tracking the S&P 100 Index, while IWM is a Small Cap Blend Equities fund tracking the Russell 2000 Index. Both are passively managed. Over the past 10 years, OEF returned 16.71%/yr vs 10.93%/yr for IWM. A 0.80 correlation means they provide meaningful diversification when combined. OEF charges 0.20%/yr vs 0.19%/yr for IWM.

Performance

OEF vs. IWM - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares S&P 100 ETF (OEF) and iShares Russell 2000 ETF (IWM). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, OEF achieves a 9.51% return, which is significantly lower than IWM's 17.07% return. Over the past 10 years, OEF has outperformed IWM with an annualized return of 16.71%, while IWM has yielded a comparatively lower 10.93% annualized return.

OEF

• 1D: -0.87%
• 1M: 5.44%
• YTD: 9.51%
• 6M: 9.34%
• 1Y: 29.54%
• 3Y*: 24.53%
• 5Y*: 15.70%
• 10Y*: 16.71%

IWM

• 1D: -1.37%
• 1M: 3.52%
• YTD: 17.07%
• 6M: 15.83%
• 1Y: 39.10%
• 3Y*: 17.88%
• 5Y*: 6.11%
• 10Y*: 10.93%

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

OEF vs. IWM - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
OEF iShares S&P 100 ETF	9.51%	19.80%	30.74%	32.71%	-21.03%	29.18%	21.21%	31.87%	-4.16%	21.82%
IWM iShares Russell 2000 ETF	17.07%	12.66%	11.38%	16.83%	-20.48%	14.54%	20.03%	25.39%	-11.12%	14.58%

Correlation

The correlation between OEF and IWM is 0.69, 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	0.69
Correlation (3Y) Calculated over the trailing 3-year period	0.67
Correlation (5Y) Calculated over the trailing 5-year period	0.75
Correlation (10Y) Calculated over the trailing 10-year period	0.75
Correlation (All Time) Calculated using the full available price history since Oct 30, 2000	0.80

The correlation between OEF and IWM shifts across timeframes, from 0.67 (3 years) to 0.80 (all time), reflecting how their relationship changes across market environments.

OEF vs. IWM - Sectors Allocation Comparison

Sectors	OEF	IWM
Technology	41.0%	19.5%
Communication Services	14.5%	2.0%
Financial Services	10.7%	15.8%
Consumer Cyclical	10.5%	7.8%
Healthcare	8.3%	15.8%
Consumer Defensive	5.4%	2.1%
Industrials	5.3%	17.1%
Energy	2.6%	6.0%
Utilities	0.9%	3.0%
Basic Materials	0.5%	4.5%
Real Estate	0.3%	5.7%

Return for Risk

OEF vs. IWM — Risk / Return Rank

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

OEF

OEF Risk / Return Rank: 64
OEF Sharpe Ratio Rank: 69
OEF Sortino Ratio Rank: 67
OEF Omega Ratio Rank: 68
OEF Calmar Ratio Rank: 53
OEF Martin Ratio Rank: 62

IWM

IWM Risk / Return Rank: 62
IWM Sharpe Ratio Rank: 59
IWM Sortino Ratio Rank: 59
IWM Omega Ratio Rank: 53
IWM Calmar Ratio Rank: 70
IWM Martin Ratio Rank: 67

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.

OEF vs. IWM - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares S&P 100 ETF (OEF) and iShares Russell 2000 ETF (IWM). 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.

	OEF	IWM	Difference
Sharpe ratio: Return per unit of total volatility	2.33	2.05	+0.28
Sortino ratio: Return per unit of downside risk	3.15	2.85	+0.30
Omega ratio: Gain probability vs. loss probability	1.42	1.34	+0.08
Calmar ratio: Return relative to maximum drawdown	2.68	3.56	-0.88
Martin ratio: Return relative to average drawdown	11.29	12.64	-1.35
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

OEF vs. IWM - Sharpe Ratio Comparison

The current OEF Sharpe Ratio is 2.33, which is comparable to the IWM Sharpe Ratio of 2.05. The chart below compares the historical Sharpe Ratios of OEF and IWM, 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

	OEF	IWM	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.33	2.05	+0.28
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.89	0.27	+0.62
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.91	0.48	+0.43
Sharpe Ratio (All Time) Calculated using the full available price history	0.45	0.37	+0.08

Drawdowns

OEF vs. IWM - Drawdown Comparison

The maximum OEF drawdown since its inception was -54.11%, smaller than the maximum IWM drawdown of -59.05%. Use the drawdown chart below to compare losses from any high point for OEF and IWM.

Drawdown Indicators

	OEF	IWM	Difference
Max Drawdown Largest peak-to-trough decline	-54.11%	-59.05%	+4.94%
Max Drawdown (1Y) Largest decline over 1 year	-11.06%	-11.03%	-0.03%
Max Drawdown (3Y) Largest decline over 3 years	-19.80%	-27.50%	+7.70%
Max Drawdown (5Y) Largest decline over 5 years	-26.47%	-31.91%	+5.44%
Max Drawdown (10Y) Largest decline over 10 years	-31.44%	-41.13%	+9.69%
Current Drawdown Current decline from peak	-0.94%	-1.49%	+0.55%
Average Drawdown Average peak-to-trough decline	-11.76%	-10.77%	-0.99%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.62%	3.10%	-0.48%

Volatility

OEF vs. IWM - Volatility Comparison

The current volatility for iShares S&P 100 ETF (OEF) is 3.14%, while iShares Russell 2000 ETF (IWM) has a volatility of 5.75%. This indicates that OEF experiences smaller price fluctuations and is considered to be less risky than IWM based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	OEF	IWM	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.14%	5.75%	-2.61%
Volatility (6M) Calculated over the trailing 6-month period	9.48%	13.53%	-4.05%
Volatility (1Y) Calculated over the trailing 1-year period	12.73%	19.20%	-6.47%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.69%	22.52%	-4.83%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.44%	23.04%	-4.60%

OEF vs. IWM - Expense Ratio Comparison

OEF has a 0.20% expense ratio, which is higher than IWM's 0.19% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

OEF vs. IWM - Dividend Comparison

OEF's dividend yield for the trailing twelve months is around 0.83%, less than IWM's 0.88% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
IWM iShares Russell 2000 ETF	0.88%	1.04%	1.15%	1.35%	1.48%	0.94%	1.04%	1.26%	1.40%	1.26%	1.38%	1.54%
OEF iShares S&P 100 ETF	0.83%	0.81%	1.03%	1.19%	1.55%	1.06%	1.43%	1.87%	2.09%	1.81%	2.07%	2.11%

Frequently Asked Questions

Can I hold both OEF and IWM in my portfolio?

OEF and IWM have a correlation of 0.69, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, OEF or IWM?

IWM has higher volatility (5.75%) compared to OEF (3.14%). In terms of maximum drawdown, OEF dropped -54.11% vs IWM's -59.05%.

Which ETF is better, OEF or IWM?

On 10-year performance, OEF leads with 16.71% vs 10.93% for IWM. On fees, IWM is cheaper at 0.19% per year. On volatility, OEF has been the lower-risk option at 3.14%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, OEF or IWM?

Over the 10-year period, OEF has performed better with a 16.71% return vs 10.93%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, OEF or IWM?

IWM is cheaper with a 0.19% expense ratio, compared with 0.20% for OEF.

Which ETF pays a higher dividend yield, OEF or IWM?

IWM has the higher dividend yield at 0.88%, compared with 0.83% for OEF.

What is the main difference between OEF and IWM?

OEF is categorized as Large Cap Blend Equities, while IWM is Small Cap Blend Equities. OEF tracks S&P 100 Index, while IWM tracks Russell 2000 Index. Their fees differ too: 0.20% for OEF and 0.19% for IWM.

Which has better risk-adjusted returns?

OEF currently has the higher Sharpe Ratio (2.33 vs 2.05), 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.