VIOO vs. IWC

Last updated Jun 3, 2026

VIOO (Vanguard S&P Small-Cap 600 ETF) and IWC (iShares Micro-Cap ETF) are both Small Cap Blend Equities funds - VIOO tracks the S&P SmallCap 600 Index while IWC tracks the Russell Microcap Index. Both are passively managed. Over the past 10 years, VIOO returned 10.77%/yr vs 11.58%/yr for IWC. Their correlation of 0.90 suggests significant overlap in exposure. VIOO charges 0.10%/yr vs 0.60%/yr for IWC.

Performance

VIOO vs. IWC - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard S&P Small-Cap 600 ETF (VIOO) and iShares Micro-Cap ETF (IWC). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VIOO achieves a 16.37% return, which is significantly lower than IWC's 21.51% return. Over the past 10 years, VIOO has underperformed IWC with an annualized return of 10.77%, while IWC has yielded a comparatively higher 11.58% annualized return.

VIOO

• 1D: 0.91%
• 1M: 1.63%
• YTD: 16.37%
• 6M: 16.85%
• 1Y: 34.98%
• 3Y*: 14.74%
• 5Y*: 5.91%
• 10Y*: 10.77%

IWC

• 1D: -0.09%
• 1M: 5.14%
• YTD: 21.51%
• 6M: 25.02%
• 1Y: 61.79%
• 3Y*: 22.59%
• 5Y*: 5.97%
• 10Y*: 11.58%

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

VIOO vs. IWC - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VIOO Vanguard S&P Small-Cap 600 ETF	16.37%	6.04%	8.48%	16.16%	-16.26%	26.79%	11.47%	22.68%	-8.65%	13.16%
IWC iShares Micro-Cap ETF	21.51%	22.45%	13.63%	8.99%	-21.93%	18.67%	20.88%	22.20%	-13.13%	12.79%

Correlation

The correlation between VIOO and IWC 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	0.88
Correlation (5Y) Calculated over the trailing 5-year period	0.90
Correlation (10Y) Calculated over the trailing 10-year period	0.91
Correlation (All Time) Calculated using the full available price history since Sep 10, 2010	0.90

The correlation between VIOO and IWC shifts across timeframes, from 0.81 (1 year) to 0.91 (10 years), reflecting how their relationship changes across market environments.

VIOO vs. IWC - Sectors Allocation Comparison

Sectors	VIOO	IWC
Financial Services	16.9%	18.1%
Industrials	15.5%	13.3%
Technology	15.5%	18.4%
Consumer Cyclical	13.4%	5.3%
Healthcare	11.0%	28.1%
Real Estate	7.7%	3.5%
Energy	5.9%	4.7%
Basic Materials	5.1%	4.4%
Communication Services	3.6%	1.8%
Consumer Defensive	3.5%	1.9%
Utilities	2.0%	0.6%

Return for Risk

VIOO vs. IWC — Risk / Return Rank

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

VIOO

VIOO Risk / Return Rank: 64
VIOO Sharpe Ratio Rank: 58
VIOO Sortino Ratio Rank: 61
VIOO Omega Ratio Rank: 55
VIOO Calmar Ratio Rank: 76
VIOO Martin Ratio Rank: 70

IWC

IWC Risk / Return Rank: 78
IWC Sharpe Ratio Rank: 80
IWC Sortino Ratio Rank: 75
IWC Omega Ratio Rank: 67
IWC Calmar Ratio Rank: 87
IWC Martin Ratio Rank: 81

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.

VIOO vs. IWC - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard S&P Small-Cap 600 ETF (VIOO) and iShares Micro-Cap ETF (IWC). 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.

	VIOO	IWC	Difference
Sharpe ratio Return per unit of total volatility	2.00	2.64	-0.64
Sortino ratio Return per unit of downside risk	2.88	3.41	-0.53
Omega ratio Gain probability vs. loss probability	1.34	1.41	-0.06
Calmar ratio Return relative to maximum drawdown	3.93	4.97	-1.04
Martin ratio Return relative to average drawdown	13.17	16.48	-3.30
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VIOO vs. IWC - Sharpe Ratio Comparison

The current VIOO Sharpe Ratio is 2.00, which is comparable to the IWC Sharpe Ratio of 2.64. The chart below compares the historical Sharpe Ratios of VIOO and IWC, 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

	VIOO	IWC	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.00	2.64	-0.64
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.28	0.25	+0.03
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.47	0.48	-0.01
Sharpe Ratio (All Time) Calculated using the full available price history	0.58	0.32	+0.26

Drawdowns

VIOO vs. IWC - Drawdown Comparison

The maximum VIOO drawdown since its inception was -44.15%, smaller than the maximum IWC drawdown of -64.61%. Use the drawdown chart below to compare losses from any high point for VIOO and IWC.

Drawdown Indicators

	VIOO	IWC	Difference
Max Drawdown Largest peak-to-trough decline	-44.15%	-64.61%	+20.46%
Max Drawdown (1Y) Largest decline over 1 year	-8.77%	-12.43%	+3.66%
Max Drawdown (3Y) Largest decline over 3 years	-27.93%	-29.46%	+1.53%
Max Drawdown (5Y) Largest decline over 5 years	-27.93%	-40.68%	+12.75%
Max Drawdown (10Y) Largest decline over 10 years	-44.15%	-47.21%	+3.06%
Current Drawdown Current decline from peak	-0.01%	-0.83%	+0.82%
Average Drawdown Average peak-to-trough decline	-7.34%	-15.28%	+7.94%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.62%	3.75%	-1.13%

Volatility

VIOO vs. IWC - Volatility Comparison

The current volatility for Vanguard S&P Small-Cap 600 ETF (VIOO) is 4.40%, while iShares Micro-Cap ETF (IWC) has a volatility of 6.90%. This indicates that VIOO experiences smaller price fluctuations and is considered to be less risky than IWC based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VIOO	IWC	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.40%	6.90%	-2.50%
Volatility (6M) Calculated over the trailing 6-month period	11.69%	17.20%	-5.51%
Volatility (1Y) Calculated over the trailing 1-year period	17.57%	23.52%	-5.95%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	21.40%	24.40%	-3.00%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	22.99%	24.42%	-1.43%

VIOO vs. IWC - Expense Ratio Comparison

VIOO has a 0.10% expense ratio, which is lower than IWC's 0.60% expense ratio.

Dividends

VIOO vs. IWC - Dividend Comparison

VIOO's dividend yield for the trailing twelve months is around 1.17%, more than IWC's 0.89% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
IWC iShares Micro-Cap ETF	0.89%	1.10%	1.06%	1.17%	1.18%	0.78%	0.98%	1.19%	1.01%	1.09%	1.16%	1.49%
VIOO Vanguard S&P Small-Cap 600 ETF	1.17%	1.36%	1.48%	1.47%	1.51%	1.16%	1.09%	1.37%	1.32%	1.11%	1.06%	1.26%

Frequently Asked Questions

Can I hold both VIOO and IWC in my portfolio?

VIOO and IWC 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, VIOO or IWC?

IWC has higher volatility (6.90%) compared to VIOO (4.40%). In terms of maximum drawdown, VIOO dropped -44.15% vs IWC's -64.61%.

Which ETF is better, VIOO or IWC?

On 10-year performance, IWC leads with 11.58% vs 10.77% for VIOO. On fees, VIOO is cheaper at 0.10% per year. On volatility, VIOO has been the lower-risk option at 4.40%. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF has performed better, VIOO or IWC?

Over the 10-year period, IWC has performed better with a 11.58% return vs 10.77%. Past performance does not guarantee future results, so compare this with risk, fees, and fund exposure.

Which ETF is cheaper, VIOO or IWC?

VIOO is cheaper with a 0.10% expense ratio, compared with 0.60% for IWC.

Which ETF pays a higher dividend yield, VIOO or IWC?

VIOO has the higher dividend yield at 1.17%, compared with 0.89% for IWC.

What is the main difference between VIOO and IWC?

VIOO tracks S&P SmallCap 600 Index, while IWC tracks Russell Microcap Index. They also come from different issuers: Vanguard and iShares. Their fees differ too: 0.10% for VIOO and 0.60% for IWC.

Which has better risk-adjusted returns?

IWC currently has the higher Sharpe Ratio (2.64 vs 2.00), 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.