VBAIX vs. AMBFX

Last updated Jun 3, 2026

VBAIX (Vanguard Balanced Index Fund Institutional Shares) and AMBFX (American Funds American Balanced Fund® Class F-2) are both Diversified Portfolio funds. Over the past 10 years, VBAIX returned 10.13%/yr vs 10.45%/yr for AMBFX. With a 0.96 correlation, they move nearly in lockstep. VBAIX charges 0.06%/yr vs 0.35%/yr for AMBFX.

Performance

VBAIX vs. AMBFX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Balanced Index Fund Institutional Shares (VBAIX) and American Funds American Balanced Fund® Class F-2 (AMBFX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VBAIX achieves a 7.22% return, which is significantly lower than AMBFX's 9.80% return. Both investments have delivered pretty close results over the past 10 years, with VBAIX having a 10.13% annualized return and AMBFX not far ahead at 10.45%.

VBAIX

• 1D: 0.13%
• 1M: 3.18%
• YTD: 7.22%
• 6M: 7.45%
• 1Y: 19.68%
• 3Y*: 16.05%
• 5Y*: 8.51%
• 10Y*: 10.13%

AMBFX

• 1D: 0.20%
• 1M: 3.59%
• YTD: 9.80%
• 6M: 10.73%
• 1Y: 25.43%
• 3Y*: 17.67%
• 5Y*: 9.84%
• 10Y*: 10.45%

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

VBAIX vs. AMBFX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VBAIX Vanguard Balanced Index Fund Institutional Shares	7.22%	13.60%	17.78%	17.55%	-16.87%	14.20%	16.40%	21.79%	-2.83%	13.86%
AMBFX American Funds American Balanced Fund® Class F-2	9.80%	18.67%	15.25%	13.81%	-11.93%	16.00%	11.06%	19.45%	-2.69%	14.85%

Correlation

The correlation between VBAIX and AMBFX is 0.94, 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	0.94
Correlation (3Y) Calculated over the trailing 3-year period	0.95
Correlation (5Y) Calculated over the trailing 5-year period	0.96
Correlation (10Y) Calculated over the trailing 10-year period	0.96
Correlation (All Time) Calculated using the full available price history since Aug 4, 2008	0.97

The correlation between VBAIX and AMBFX has been stable across timeframes, ranging from 0.94 to 0.96 - a consistent structural relationship.

Return for Risk

VBAIX vs. AMBFX — Risk / Return Rank

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

VBAIX

VBAIX Risk / Return Rank: 76
VBAIX Sharpe Ratio Rank: 76
VBAIX Sortino Ratio Rank: 74
VBAIX Omega Ratio Rank: 70
VBAIX Calmar Ratio Rank: 75
VBAIX Martin Ratio Rank: 83

AMBFX

AMBFX Risk / Return Rank: 86
AMBFX Sharpe Ratio Rank: 90
AMBFX Sortino Ratio Rank: 87
AMBFX Omega Ratio Rank: 84
AMBFX Calmar Ratio Rank: 81
AMBFX Martin Ratio Rank: 87

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.

VBAIX vs. AMBFX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Balanced Index Fund Institutional Shares (VBAIX) and American Funds American Balanced Fund® Class F-2 (AMBFX). 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.

	VBAIX	AMBFX	Difference
Sharpe ratio Return per unit of total volatility	2.52	2.98	-0.46
Sortino ratio Return per unit of downside risk	3.60	4.17	-0.57
Omega ratio Gain probability vs. loss probability	1.47	1.57	-0.10
Calmar ratio Return relative to maximum drawdown	3.42	3.72	-0.30
Martin ratio Return relative to average drawdown	15.65	16.88	-1.22
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VBAIX vs. AMBFX - Sharpe Ratio Comparison

The current VBAIX Sharpe Ratio is 2.52, which is comparable to the AMBFX Sharpe Ratio of 2.98. The chart below compares the historical Sharpe Ratios of VBAIX and AMBFX, 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

	VBAIX	AMBFX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.52	2.98	-0.46
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.77	0.94	-0.17
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.91	0.98	-0.08
Sharpe Ratio (All Time) Calculated using the full available price history	0.66	0.78	-0.12

Drawdowns

VBAIX vs. AMBFX - Drawdown Comparison

The maximum VBAIX drawdown since its inception was -35.82%, roughly equal to the maximum AMBFX drawdown of -35.05%. Use the drawdown chart below to compare losses from any high point for VBAIX and AMBFX.

Drawdown Indicators

	VBAIX	AMBFX	Difference
Max Drawdown Largest peak-to-trough decline	-35.82%	-35.05%	-0.77%
Max Drawdown (1Y) Largest decline over 1 year	-5.84%	-7.00%	+1.16%
Max Drawdown (3Y) Largest decline over 3 years	-11.57%	-10.64%	-0.93%
Max Drawdown (5Y) Largest decline over 5 years	-21.52%	-18.65%	-2.87%
Max Drawdown (10Y) Largest decline over 10 years	-22.77%	-22.31%	-0.46%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-4.42%	-3.58%	-0.84%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.27%	1.54%	-0.27%

Volatility

VBAIX vs. AMBFX - Volatility Comparison

The current volatility for Vanguard Balanced Index Fund Institutional Shares (VBAIX) is 2.26%, while American Funds American Balanced Fund® Class F-2 (AMBFX) has a volatility of 2.67%. This indicates that VBAIX experiences smaller price fluctuations and is considered to be less risky than AMBFX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VBAIX	AMBFX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.26%	2.67%	-0.41%
Volatility (6M) Calculated over the trailing 6-month period	6.12%	6.87%	-0.75%
Volatility (1Y) Calculated over the trailing 1-year period	7.91%	8.74%	-0.83%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	11.10%	10.50%	+0.60%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	11.23%	10.67%	+0.56%

VBAIX vs. AMBFX - Expense Ratio Comparison

VBAIX has a 0.06% expense ratio, which is lower than AMBFX's 0.35% expense ratio.

Dividends

VBAIX vs. AMBFX - Dividend Comparison

VBAIX's dividend yield for the trailing twelve months is around 5.23%, less than AMBFX's 7.74% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AMBFX American Funds American Balanced Fund® Class F-2	7.74%	8.47%	7.40%	2.20%	2.52%	4.50%	4.56%	4.19%	6.20%	4.85%	4.46%	5.81%
VBAIX Vanguard Balanced Index Fund Institutional Shares	5.23%	6.01%	8.01%	4.36%	2.84%	3.20%	2.65%	2.29%	2.33%	1.96%	2.10%	2.10%

Frequently Asked Questions

Can I hold both VBAIX and AMBFX in my portfolio?

With a correlation of 0.94, VBAIX and AMBFX 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, VBAIX or AMBFX?

AMBFX has higher volatility (2.67%) compared to VBAIX (2.26%). In terms of maximum drawdown, VBAIX dropped -35.82% vs AMBFX's -35.05%.

Which has better risk-adjusted returns?

AMBFX currently has the higher Sharpe Ratio (2.98 vs 2.52), 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.