MBBA vs. IWM

Last updated Jun 25, 2026

MBBA (iShares Mortgage-Backed Securities Active ETF) and IWM (iShares Russell 2000 ETF) are both exchange-traded funds - MBBA is a Mortgage Backed Securities fund actively managed by iShares, while IWM is a Small Cap Blend Equities fund tracking the Russell 2000 Index. MBBA is actively managed, while IWM is passively managed. At a 0.49 correlation, their price movements are largely independent. MBBA charges 0.25%/yr vs 0.19%/yr for IWM.

Performance

MBBA vs. IWM - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Mortgage-Backed Securities Active ETF (MBBA) and iShares Russell 2000 ETF (IWM). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

MBBA

• 1D: 0.38%
• 1M: 1.26%
• YTD: —
• 6M: —
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —

IWM

• 1D: 0.46%
• 1M: 4.31%
• YTD: 21.03%
• 6M: 17.89%
• 1Y: 39.77%
• 3Y*: 19.40%
• 5Y*: 6.33%
• 10Y*: 11.63%

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

MBBA vs. IWM - Yearly Performance Comparison

	2026 (YTD)
MBBA iShares Mortgage-Backed Securities Active ETF	1.27%
IWM iShares Russell 2000 ETF	12.51%

Correlation

The correlation between MBBA and IWM is 0.49, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (All Time) Calculated using the full available price history since Jan 26, 2026	0.49

Return for Risk

MBBA vs. IWM — Risk / Return Rank

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

MBBA

Risk / return metrics aren't available yet — we need at least 12 months of trading data to calculate them.

IWM

IWM Risk / Return Rank: 70
IWM Sharpe Ratio Rank: 70
IWM Sortino Ratio Rank: 69
IWM Omega Ratio Rank: 61
IWM Calmar Ratio Rank: 77
IWM 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.

MBBA vs. IWM - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Mortgage-Backed Securities Active ETF (MBBA) 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.

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.

	MBBA	IWM	Difference
Sharpe ratio: Return per unit of total volatility	—	2.03	—
Sortino ratio: Return per unit of downside risk	—	2.80	—
Omega ratio: Gain probability vs. loss probability	—	1.33	—
Calmar ratio: Return relative to maximum drawdown	—	3.62	—
Martin ratio: Return relative to average drawdown	—	12.82	—

Drawdowns

MBBA vs. IWM - Drawdown Comparison

The maximum MBBA drawdown since its inception was -2.83%, smaller than the maximum IWM drawdown of -59.05%. Use the drawdown chart below to compare losses from any high point for MBBA and IWM.

Drawdown Indicators

	MBBA	IWM	Difference
Max Drawdown Largest peak-to-trough decline	-2.83%	-59.05%	+56.22%
Max Drawdown (1Y) Largest decline over 1 year	—	-11.03%	—
Max Drawdown (3Y) Largest decline over 3 years	—	-27.50%	—
Max Drawdown (5Y) Largest decline over 5 years	—	-31.91%	—
Max Drawdown (10Y) Largest decline over 10 years	—	-41.13%	—
Current Drawdown Current decline from peak	-0.72%	-0.50%	-0.22%
Average Drawdown Average peak-to-trough decline	-1.12%	-10.74%	+9.62%
Ulcer Index Depth and duration of drawdowns from previous peaks	—	3.11%	—

Volatility

Volatility by Period

	MBBA	IWM	Difference
Volatility (1M) Calculated over the trailing 1-month period	—	6.52%	—
Volatility (6M) Calculated over the trailing 6-month period	—	14.30%	—
Volatility (1Y) Calculated over the trailing 1-year period	4.55%	19.71%	-15.16%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	4.55%	22.60%	-18.05%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.55%	23.06%	-18.51%

MBBA vs. IWM - Expense Ratio Comparison

MBBA has a 0.25% 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

MBBA vs. IWM - Dividend Comparison

MBBA's dividend yield for the trailing twelve months is around 1.83%, more than IWM's 0.90% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
IWM iShares Russell 2000 ETF	0.90%	1.04%	1.15%	1.35%	1.48%	0.94%	1.04%	1.26%	1.40%	1.26%	1.38%	1.54%
MBBA iShares Mortgage-Backed Securities Active ETF	1.83%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both MBBA and IWM in my portfolio?

MBBA and IWM have a correlation of 0.49, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which ETF is better, MBBA or IWM?

On fees, IWM is cheaper at 0.19% per year. The better choice depends on whether you care most about return, fees, risk, or income.

Which ETF is cheaper, MBBA or IWM?

IWM is cheaper with a 0.19% expense ratio, compared with 0.25% for MBBA.

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

MBBA has the higher dividend yield at 1.83%, compared with 0.90% for IWM.

What is the main difference between MBBA and IWM?

MBBA is categorized as Mortgage Backed Securities, while IWM is Small Cap Blend Equities. Their fees differ too: 0.25% for MBBA and 0.19% for IWM.