BDBKX vs. BASMX

Last updated Apr 1, 2026

Compare and contrast key facts about iShares Russell 2000 Small-Cap Index Fund Class K (BDBKX) and iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX).

BDBKX is a passively managed fund by iShares that tracks the performance of the Russell 2000 Index. It was launched on Apr 1, 2011. BASMX is a passively managed fund by iShares that tracks the performance of the Russell 3000 Index. It was launched on Aug 13, 2015. Both BDBKX and BASMX are passive ETFs, meaning that they are not actively managed but aim to replicate the performance of the underlying index as closely as possible.

Performance

BDBKX vs. BASMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares Russell 2000 Small-Cap Index Fund Class K (BDBKX) and iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX). The values are adjusted to include any dividend payments, if applicable.

BDBKX vs. BASMX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
BDBKX iShares Russell 2000 Small-Cap Index Fund Class K	-2.46%	12.81%	11.40%	17.04%	-20.32%	14.59%	20.02%	25.66%	-11.01%	14.71%
BASMX iShares Total U.S. Stock Market Index Fund Investor A Shares	-6.77%	16.81%	23.46%	25.63%	-19.32%	25.26%	20.37%	30.71%	-5.57%	20.65%

Returns By Period

In the year-to-date period, BDBKX achieves a -2.46% return, which is significantly higher than BASMX's -6.77% return. Over the past 10 years, BDBKX has underperformed BASMX with an annualized return of 9.49%, while BASMX has yielded a comparatively higher 12.98% annualized return.

BDBKX

• 1D: -1.43%
• 1M: -8.15%
• YTD: -2.46%
• 6M: -0.33%
• 1Y: 21.55%
• 3Y*: 11.76%
• 5Y*: 3.06%
• 10Y*: 9.49%

BASMX

• 1D: -0.45%
• 1M: -7.72%
• YTD: -6.77%
• 6M: -4.59%
• 1Y: 14.36%
• 3Y*: 16.39%
• 5Y*: 9.94%
• 10Y*: 12.98%

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

BDBKX vs. BASMX - Expense Ratio Comparison

BDBKX has a 0.07% expense ratio, which is lower than BASMX's 0.33% expense ratio.

BASMX

iShares Total U.S. Stock Market Index Fund Investor A Shares

BDBKX

iShares Russell 2000 Small-Cap Index Fund Class K

Return for Risk

BDBKX vs. BASMX — Risk / Return Rank

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

BDBKX

BDBKX Risk / Return Rank: 46
BDBKX Sharpe Ratio Rank: 43
BDBKX Sortino Ratio Rank: 47
BDBKX Omega Ratio Rank: 36
BDBKX Calmar Ratio Rank: 54
BDBKX Martin Ratio Rank: 51

BASMX

BASMX Risk / Return Rank: 40
BASMX Sharpe Ratio Rank: 35
BASMX Sortino Ratio Rank: 38
BASMX Omega Ratio Rank: 41
BASMX Calmar Ratio Rank: 37
BASMX Martin Ratio Rank: 49

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.

BDBKX vs. BASMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares Russell 2000 Small-Cap Index Fund Class K (BDBKX) and iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX). 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.

	BDBKX	BASMX	Difference
Sharpe ratio Return per unit of total volatility	0.91	0.81	+0.10
Sortino ratio Return per unit of downside risk	1.40	1.27	+0.13
Omega ratio Gain probability vs. loss probability	1.18	1.19	-0.01
Calmar ratio Return relative to maximum drawdown	1.33	1.02	+0.31
Martin ratio Return relative to average drawdown	5.03	4.92	+0.11
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

BDBKX vs. BASMX - Sharpe Ratio Comparison

The current BDBKX Sharpe Ratio is 0.91, which is comparable to the BASMX Sharpe Ratio of 0.81. The chart below compares the historical Sharpe Ratios of BDBKX and BASMX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	BDBKX	BASMX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.91	0.81	+0.10
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.13	0.58	-0.44
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.40	0.71	-0.31
Sharpe Ratio (All Time) Calculated using the full available price history	0.38	0.71	-0.33

Correlation

The correlation between BDBKX and BASMX is 0.86, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.

Dividends

BDBKX vs. BASMX - Dividend Comparison

BDBKX's dividend yield for the trailing twelve months is around 3.25%, more than BASMX's 0.92% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BDBKX iShares Russell 2000 Small-Cap Index Fund Class K	3.25%	3.17%	4.84%	2.96%	1.76%	7.67%	1.45%	3.47%	4.29%	3.18%	4.62%	3.64%
BASMX iShares Total U.S. Stock Market Index Fund Investor A Shares	0.92%	0.86%	0.99%	1.19%	1.33%	1.33%	1.20%	1.90%	2.18%	1.93%	1.37%	0.00%

Drawdowns

BDBKX vs. BASMX - Drawdown Comparison

The maximum BDBKX drawdown since its inception was -41.66%, which is greater than BASMX's maximum drawdown of -34.95%. Use the drawdown chart below to compare losses from any high point for BDBKX and BASMX.

Drawdown Indicators

	BDBKX	BASMX	Difference
Max Drawdown Largest peak-to-trough decline	-41.66%	-34.95%	-6.71%
Max Drawdown (1Y) Largest decline over 1 year	-13.89%	-12.39%	-1.50%
Max Drawdown (5Y) Largest decline over 5 years	-31.96%	-25.12%	-6.84%
Max Drawdown (10Y) Largest decline over 10 years	-41.66%	-34.95%	-6.71%
Current Drawdown Current decline from peak	-10.97%	-8.92%	-2.05%
Average Drawdown Average peak-to-trough decline	-8.83%	-4.65%	-4.18%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.67%	2.56%	+1.11%

Volatility

BDBKX vs. BASMX - Volatility Comparison

iShares Russell 2000 Small-Cap Index Fund Class K (BDBKX) has a higher volatility of 6.59% compared to iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX) at 4.39%. This indicates that BDBKX's price experiences larger fluctuations and is considered to be riskier than BASMX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BDBKX	BASMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.59%	4.39%	+2.20%
Volatility (6M) Calculated over the trailing 6-month period	14.10%	9.28%	+4.82%
Volatility (1Y) Calculated over the trailing 1-year period	23.12%	18.39%	+4.73%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	23.15%	17.34%	+5.81%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.65%	18.37%	+5.28%