BASMX vs. BKTSX

Last updated Apr 1, 2026

Compare and contrast key facts about iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX) and iShares Total U.S. Stock Market Index Fund Class K (BKTSX).

BASMX is a passively managed fund by iShares that tracks the performance of the Russell 3000 Index. It was launched on Aug 13, 2015. BKTSX is a passively managed fund by iShares that tracks the performance of the Russell 3000 Index. It was launched on Aug 13, 2015. Both BASMX and BKTSX 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

BASMX vs. BKTSX - Performance Comparison

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

BASMX vs. BKTSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
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%
BKTSX iShares Total U.S. Stock Market Index Fund Class K	-6.70%	17.15%	23.83%	26.02%	-19.05%	25.56%	20.82%	31.12%	-5.37%	21.02%

Returns By Period

The year-to-date returns for both investments are quite close, with BASMX having a -6.77% return and BKTSX slightly higher at -6.70%. Both investments have delivered pretty close results over the past 10 years, with BASMX having a 12.98% annualized return and BKTSX not far ahead at 13.31%.

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%

BKTSX

• 1D: -0.45%
• 1M: -7.71%
• YTD: -6.70%
• 6M: -4.47%
• 1Y: 14.73%
• 3Y*: 16.75%
• 5Y*: 10.27%
• 10Y*: 13.31%

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

BASMX vs. BKTSX - Expense Ratio Comparison

BASMX has a 0.33% expense ratio, which is higher than BKTSX's 0.02% expense ratio.

BASMX

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

BKTSX

iShares Total U.S. Stock Market Index Fund Class K

Return for Risk

BASMX vs. BKTSX — Risk / Return Rank

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

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

BKTSX

BKTSX Risk / Return Rank: 42
BKTSX Sharpe Ratio Rank: 38
BKTSX Sortino Ratio Rank: 40
BKTSX Omega Ratio Rank: 43
BKTSX Calmar Ratio Rank: 39
BKTSX Martin Ratio Rank: 52

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.

BASMX vs. BKTSX - Risk-Adjusted Trends Comparison

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

	BASMX	BKTSX	Difference
Sharpe ratio Return per unit of total volatility	0.81	0.83	-0.02
Sortino ratio Return per unit of downside risk	1.27	1.29	-0.03
Omega ratio Gain probability vs. loss probability	1.19	1.20	0.00
Calmar ratio Return relative to maximum drawdown	1.02	1.05	-0.03
Martin ratio Return relative to average drawdown	4.92	5.09	-0.17
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

BASMX vs. BKTSX - Sharpe Ratio Comparison

The current BASMX Sharpe Ratio is 0.81, which is comparable to the BKTSX Sharpe Ratio of 0.83. The chart below compares the historical Sharpe Ratios of BASMX and BKTSX, 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

	BASMX	BKTSX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.81	0.83	-0.02
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.58	0.60	-0.02
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.71	0.73	-0.02
Sharpe Ratio (All Time) Calculated using the full available price history	0.71	0.73	-0.02

Correlation

The correlation between BASMX and BKTSX is 1.00, 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

BASMX vs. BKTSX - Dividend Comparison

BASMX's dividend yield for the trailing twelve months is around 0.92%, less than BKTSX's 1.22% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016
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%
BKTSX iShares Total U.S. Stock Market Index Fund Class K	1.22%	1.14%	1.27%	1.46%	1.64%	1.58%	1.51%	2.15%	2.49%	2.17%	1.54%

Drawdowns

BASMX vs. BKTSX - Drawdown Comparison

The maximum BASMX drawdown since its inception was -34.95%, roughly equal to the maximum BKTSX drawdown of -34.97%. Use the drawdown chart below to compare losses from any high point for BASMX and BKTSX.

Drawdown Indicators

	BASMX	BKTSX	Difference
Max Drawdown Largest peak-to-trough decline	-34.95%	-34.97%	+0.02%
Max Drawdown (1Y) Largest decline over 1 year	-12.39%	-12.36%	-0.03%
Max Drawdown (5Y) Largest decline over 5 years	-25.12%	-24.98%	-0.14%
Max Drawdown (10Y) Largest decline over 10 years	-34.95%	-34.97%	+0.02%
Current Drawdown Current decline from peak	-8.92%	-8.87%	-0.05%
Average Drawdown Average peak-to-trough decline	-4.65%	-4.59%	-0.06%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.56%	2.55%	+0.01%

Volatility

BASMX vs. BKTSX - Volatility Comparison

iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX) and iShares Total U.S. Stock Market Index Fund Class K (BKTSX) have volatilities of 4.39% and 4.37%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BASMX	BKTSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.39%	4.37%	+0.02%
Volatility (6M) Calculated over the trailing 6-month period	9.28%	9.28%	0.00%
Volatility (1Y) Calculated over the trailing 1-year period	18.39%	18.38%	+0.01%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.34%	17.33%	+0.01%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.37%	18.38%	-0.01%