BSPIX vs. BASMX

Last updated Jun 4, 2026

BSPIX (iShares S&P 500 Index Fund Institutional Class) and BASMX (iShares Total U.S. Stock Market Index Fund Investor A Shares) are both mutual funds - BSPIX is a S&P 500 fund tracking the S&P 500 Index, while BASMX is a Large Cap Blend Equities fund tracking the Russell 3000 Index. Both are passively managed. Over the past 10 years, BSPIX returned 15.46%/yr vs 14.79%/yr for BASMX. With a 0.99 correlation, they move nearly in lockstep. BSPIX charges 0.10%/yr vs 0.33%/yr for BASMX.

Performance

BSPIX vs. BASMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares S&P 500 Index Fund Institutional Class (BSPIX) and iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both stocks are quite close, with BSPIX having a 11.65% return and BASMX slightly lower at 11.60%. Both investments have delivered pretty close results over the past 10 years, with BSPIX having a 15.46% annualized return and BASMX not far behind at 14.79%.

BSPIX

• 1D: 0.13%
• 1M: 5.79%
• YTD: 11.65%
• 6M: 11.68%
• 1Y: 28.84%
• 3Y*: 22.63%
• 5Y*: 14.17%
• 10Y*: 15.46%

BASMX

• 1D: 0.23%
• 1M: 5.66%
• YTD: 11.60%
• 6M: 11.46%
• 1Y: 28.31%
• 3Y*: 21.93%
• 5Y*: 12.79%
• 10Y*: 14.79%

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

BSPIX vs. BASMX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
BSPIX iShares S&P 500 Index Fund Institutional Class	11.65%	17.75%	24.85%	26.17%	-18.20%	28.55%	18.35%	31.35%	-4.87%	21.20%
BASMX iShares Total U.S. Stock Market Index Fund Investor A Shares	11.60%	16.81%	23.46%	25.63%	-19.32%	25.26%	20.37%	30.71%	-5.57%	20.65%

Correlation

The correlation between BSPIX and BASMX is 0.99 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.99
Correlation (3Y) Calculated over the trailing 3-year period	0.98
Correlation (5Y) Calculated over the trailing 5-year period	0.99
Correlation (10Y) Calculated over the trailing 10-year period	0.99
Correlation (All Time) Calculated using the full available price history since Jan 5, 2016	0.99

The correlation between BSPIX and BASMX has been stable across timeframes, ranging from 0.98 to 0.99 - a consistent structural relationship.

Return for Risk

BSPIX vs. BASMX — Risk / Return Rank

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

BSPIX

BSPIX Risk / Return Rank: 73
BSPIX Sharpe Ratio Rank: 74
BSPIX Sortino Ratio Rank: 67
BSPIX Omega Ratio Rank: 67
BSPIX Calmar Ratio Rank: 74
BSPIX Martin Ratio Rank: 83

BASMX

BASMX Risk / Return Rank: 68
BASMX Sharpe Ratio Rank: 68
BASMX Sortino Ratio Rank: 62
BASMX Omega Ratio Rank: 61
BASMX Calmar Ratio Rank: 71
BASMX Martin Ratio Rank: 80

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.

BSPIX vs. BASMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares S&P 500 Index Fund Institutional Class (BSPIX) 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.

	BSPIX	BASMX	Difference
Sharpe ratio Return per unit of total volatility	2.51	2.41	+0.09
Sortino ratio Return per unit of downside risk	3.41	3.30	+0.11
Omega ratio Gain probability vs. loss probability	1.46	1.43	+0.02
Calmar ratio Return relative to maximum drawdown	3.34	3.29	+0.05
Martin ratio Return relative to average drawdown	15.58	15.07	+0.51
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

BSPIX vs. BASMX - Sharpe Ratio Comparison

The current BSPIX Sharpe Ratio is 2.51, which is comparable to the BASMX Sharpe Ratio of 2.41. The chart below compares the historical Sharpe Ratios of BSPIX and BASMX, 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

	BSPIX	BASMX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.51	2.41	+0.09
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.84	0.74	+0.10
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.86	0.81	+0.05
Sharpe Ratio (All Time) Calculated using the full available price history	0.81	0.81	0.00

Drawdowns

BSPIX vs. BASMX - Drawdown Comparison

The maximum BSPIX drawdown since its inception was -33.75%, roughly equal to the maximum BASMX drawdown of -34.95%. Use the drawdown chart below to compare losses from any high point for BSPIX and BASMX.

Drawdown Indicators

	BSPIX	BASMX	Difference
Max Drawdown Largest peak-to-trough decline	-33.75%	-34.95%	+1.20%
Max Drawdown (1Y) Largest decline over 1 year	-8.91%	-8.92%	+0.01%
Max Drawdown (3Y) Largest decline over 3 years	-18.74%	-19.32%	+0.58%
Max Drawdown (5Y) Largest decline over 5 years	-24.55%	-25.12%	+0.57%
Max Drawdown (10Y) Largest decline over 10 years	-33.75%	-34.95%	+1.20%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-3.93%	-4.59%	+0.66%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.90%	1.94%	-0.04%

Volatility

BSPIX vs. BASMX - Volatility Comparison

iShares S&P 500 Index Fund Institutional Class (BSPIX) and iShares Total U.S. Stock Market Index Fund Investor A Shares (BASMX) have volatilities of 2.83% and 2.94%, 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

	BSPIX	BASMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.83%	2.94%	-0.11%
Volatility (6M) Calculated over the trailing 6-month period	8.97%	9.15%	-0.18%
Volatility (1Y) Calculated over the trailing 1-year period	11.85%	12.14%	-0.29%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.88%	17.38%	-0.50%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.03%	18.41%	-0.38%

BSPIX vs. BASMX - Expense Ratio Comparison

BSPIX has a 0.10% expense ratio, which is lower than BASMX's 0.33% expense ratio.

Dividends

BSPIX vs. BASMX - Dividend Comparison

BSPIX's dividend yield for the trailing twelve months is around 1.50%, more than BASMX's 0.78% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BASMX iShares Total U.S. Stock Market Index Fund Investor A Shares	0.78%	0.86%	0.99%	1.19%	1.33%	1.33%	1.20%	1.90%	2.18%	1.93%	1.37%	0.00%
BSPIX iShares S&P 500 Index Fund Institutional Class	1.50%	1.66%	1.35%	1.44%	1.94%	1.76%	1.60%	1.92%	1.94%	1.57%	2.30%	2.42%

Frequently Asked Questions

Can I hold both BSPIX and BASMX in my portfolio?

With a correlation of 0.99, BSPIX and BASMX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, BSPIX or BASMX?

BASMX has higher volatility (2.94%) compared to BSPIX (2.83%). In terms of maximum drawdown, BSPIX dropped -33.75% vs BASMX's -34.95%.

Which has better risk-adjusted returns?

BSPIX currently has the higher Sharpe Ratio (2.51 vs 2.41), 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.