IWO vs. ACWI

Last updated Jun 5, 2026

IWO (iShares Russell 2000 Growth ETF) and ACWI (iShares MSCI ACWI ETF) are both exchange-traded funds - IWO is a Small Cap Growth Equities fund tracking the Russell 2000 Growth Index, while ACWI is a Global Equities fund tracking the MSCI All Country World Index. Both are passively managed. Over the past 10 years, IWO returned 11.28%/yr vs 12.82%/yr for ACWI. Their correlation of 0.82 suggests significant overlap in exposure. IWO charges 0.24%/yr vs 0.32%/yr for ACWI.

Performance

IWO vs. ACWI - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Russell 2000 Growth ETF (IWO) and iShares MSCI ACWI ETF (ACWI). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, IWO achieves a 18.58% return, which is significantly higher than ACWI's 12.47% return. Over the past 10 years, IWO has underperformed ACWI with an annualized return of 11.28%, while ACWI has yielded a comparatively higher 12.82% annualized return.

IWO

• 1D: 1.57%
• 1M: 3.99%
• YTD: 18.58%
• 6M: 15.22%
• 1Y: 39.51%
• 3Y*: 19.07%
• 5Y*: 5.89%
• 10Y*: 11.28%

ACWI

• 1D: 0.30%
• 1M: 4.45%
• YTD: 12.47%
• 6M: 13.07%
• 1Y: 29.24%
• 3Y*: 21.38%
• 5Y*: 11.35%
• 10Y*: 12.82%

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

IWO vs. ACWI - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
IWO iShares Russell 2000 Growth ETF	18.58%	12.90%	15.04%	18.51%	-26.27%	2.54%	34.68%	28.48%	-9.43%	22.25%
ACWI iShares MSCI ACWI ETF	12.47%	22.41%	17.45%	22.27%	-18.39%	18.66%	16.34%	26.59%	-9.19%	24.33%

Correlation

The correlation between IWO and ACWI is 0.81, 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	0.81
Correlation (3Y) Calculated over the trailing 3-year period	0.82
Correlation (5Y) Calculated over the trailing 5-year period	0.85
Correlation (10Y) Calculated over the trailing 10-year period	0.82
Correlation (All Time) Calculated using the full available price history since Mar 31, 2008	0.82

The correlation between IWO and ACWI has been stable across timeframes, ranging from 0.81 to 0.85 - a consistent structural relationship.

IWO vs. ACWI - Sectors Allocation Comparison

Sectors	IWO	ACWI
Technology	23.6%	29.4%
Industrials	23.1%	10.9%
Healthcare	22.4%	8.1%
Financial Services	8.2%	16.1%
Consumer Cyclical	7.7%	9.3%
Basic Materials	4.2%	3.7%
Energy	3.5%	4.2%
Consumer Defensive	2.6%	5.0%
Communication Services	2.2%	9.0%
Real Estate	2.1%	1.8%
Utilities	0.7%	2.6%

Return for Risk

IWO vs. ACWI — Risk / Return Rank

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

IWO

IWO Risk / Return Rank: 54
IWO Sharpe Ratio Rank: 56
IWO Sortino Ratio Rank: 54
IWO Omega Ratio Rank: 50
IWO Calmar Ratio Rank: 55
IWO Martin Ratio Rank: 56

ACWI

ACWI Risk / Return Rank: 70
ACWI Sharpe Ratio Rank: 71
ACWI Sortino Ratio Rank: 71
ACWI Omega Ratio Rank: 71
ACWI Calmar Ratio Rank: 62
ACWI Martin Ratio Rank: 73

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.

IWO vs. ACWI - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Russell 2000 Growth ETF (IWO) and iShares MSCI ACWI ETF (ACWI). 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.

	IWO	ACWI	Difference
Sharpe ratio: Return per unit of total volatility	1.86	2.30	-0.44
Sortino ratio: Return per unit of downside risk	2.55	3.17	-0.62
Omega ratio: Gain probability vs. loss probability	1.30	1.42	-0.11
Calmar ratio: Return relative to maximum drawdown	2.67	3.02	-0.35
Martin ratio: Return relative to average drawdown	9.58	13.55	-3.98
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

IWO vs. ACWI - Sharpe Ratio Comparison

The current IWO Sharpe Ratio is 1.86, which is comparable to the ACWI Sharpe Ratio of 2.30. The chart below compares the historical Sharpe Ratios of IWO and ACWI, 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

	IWO	ACWI	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.86	2.30	-0.44
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.24	0.71	-0.47
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.47	0.75	-0.28
Sharpe Ratio (All Time) Calculated using the full available price history	0.29	0.43	-0.14

Drawdowns

IWO vs. ACWI - Drawdown Comparison

The maximum IWO drawdown since its inception was -60.11%, which is greater than ACWI's maximum drawdown of -56.00%. Use the drawdown chart below to compare losses from any high point for IWO and ACWI.

Drawdown Indicators

	IWO	ACWI	Difference
Max Drawdown Largest peak-to-trough decline	-60.11%	-56.00%	-4.11%
Max Drawdown (1Y) Largest decline over 1 year	-14.87%	-9.73%	-5.14%
Max Drawdown (3Y) Largest decline over 3 years	-28.57%	-16.55%	-12.02%
Max Drawdown (5Y) Largest decline over 5 years	-40.51%	-26.42%	-14.09%
Max Drawdown (10Y) Largest decline over 10 years	-42.02%	-33.53%	-8.49%
Current Drawdown Current decline from peak	0.00%	-0.53%	+0.53%
Average Drawdown Average peak-to-trough decline	-16.70%	-8.61%	-8.09%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.14%	2.16%	+1.98%

Volatility

IWO vs. ACWI - Volatility Comparison

iShares Russell 2000 Growth ETF (IWO) has a higher volatility of 6.54% compared to iShares MSCI ACWI ETF (ACWI) at 3.83%. This indicates that IWO's price experiences larger fluctuations and is considered to be riskier than ACWI based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	IWO	ACWI	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.54%	3.83%	+2.71%
Volatility (6M) Calculated over the trailing 6-month period	15.72%	10.30%	+5.42%
Volatility (1Y) Calculated over the trailing 1-year period	21.33%	12.79%	+8.54%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	24.49%	16.05%	+8.44%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	24.13%	17.11%	+7.02%

IWO vs. ACWI - Expense Ratio Comparison

IWO has a 0.24% expense ratio, which is lower than ACWI's 0.32% expense ratio.

Dividends

IWO vs. ACWI - Dividend Comparison

IWO's dividend yield for the trailing twelve months is around 0.39%, less than ACWI's 1.38% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ACWI iShares MSCI ACWI ETF	1.38%	1.55%	1.70%	1.88%	1.79%	1.71%	1.43%	2.33%	2.18%	1.94%	2.19%	2.56%
IWO iShares Russell 2000 Growth ETF	0.39%	0.56%	0.80%	0.73%	0.73%	0.32%	0.44%	0.71%	0.76%	0.73%	0.97%	0.89%

Frequently Asked Questions

Can I hold both IWO and ACWI in my portfolio?

IWO and ACWI have a correlation of 0.81, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, IWO or ACWI?

IWO has higher volatility (6.54%) compared to ACWI (3.83%). In terms of maximum drawdown, IWO dropped -60.11% vs ACWI's -56.00%.

Which ETF is better, IWO or ACWI?

On 10-year performance, ACWI leads with 12.82% vs 11.28% for IWO. On fees, IWO is cheaper at 0.24% per year. On volatility, ACWI has been the lower-risk option at 3.83%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, IWO or ACWI?

Over the 10-year period, ACWI has performed better with a 12.82% return vs 11.28%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, IWO or ACWI?

IWO is cheaper with a 0.24% expense ratio, compared with 0.32% for ACWI.

Which ETF pays a higher dividend yield, IWO or ACWI?

ACWI has the higher dividend yield at 1.38%, compared with 0.39% for IWO.

What is the main difference between IWO and ACWI?

IWO is categorized as Small Cap Growth Equities, while ACWI is Global Equities. IWO tracks Russell 2000 Growth Index, while ACWI tracks MSCI All Country World Index. Their fees differ too: 0.24% for IWO and 0.32% for ACWI.

Which has better risk-adjusted returns?

ACWI currently has the higher Sharpe Ratio (2.30 vs 1.86), 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.