AMCPX vs. VIGIX

Last updated Jun 4, 2026

AMCPX (American Funds AMCAP Fund Class A) and VIGIX (Vanguard Growth Index Fund Institutional Shares) are both Large Cap Growth Equities funds. Over the past 10 years, AMCPX returned 12.36%/yr vs 18.40%/yr for VIGIX. Their correlation of 0.94 suggests significant overlap in exposure. AMCPX charges 0.65%/yr vs 0.04%/yr for VIGIX.

Performance

AMCPX vs. VIGIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Funds AMCAP Fund Class A (AMCPX) and Vanguard Growth Index Fund Institutional Shares (VIGIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, AMCPX achieves a 6.34% return, which is significantly lower than VIGIX's 10.83% return. Over the past 10 years, AMCPX has underperformed VIGIX with an annualized return of 12.36%, while VIGIX has yielded a comparatively higher 18.40% annualized return.

AMCPX

• 1D: -0.77%
• 1M: 3.82%
• YTD: 6.34%
• 6M: 6.01%
• 1Y: 21.86%
• 3Y*: 19.82%
• 5Y*: 9.39%
• 10Y*: 12.36%

VIGIX

• 1D: -0.28%
• 1M: 7.55%
• YTD: 10.83%
• 6M: 10.12%
• 1Y: 29.46%
• 3Y*: 26.47%
• 5Y*: 15.72%
• 10Y*: 18.40%

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

AMCPX vs. VIGIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
AMCPX American Funds AMCAP Fund Class A	6.34%	17.68%	21.11%	31.04%	-28.67%	20.57%	21.42%	26.35%	-4.42%	22.08%
VIGIX Vanguard Growth Index Fund Institutional Shares	10.83%	19.44%	32.68%	46.77%	-33.13%	27.27%	40.19%	37.26%	-3.34%	27.81%

Correlation

The correlation between AMCPX and VIGIX is 0.93, 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	0.93
Correlation (3Y) Calculated over the trailing 3-year period	0.92
Correlation (5Y) Calculated over the trailing 5-year period	0.94
Correlation (10Y) Calculated over the trailing 10-year period	0.94
Correlation (All Time) Calculated using the full available price history since May 15, 1998	0.94

The correlation between AMCPX and VIGIX has been stable across timeframes, ranging from 0.92 to 0.94 - a consistent structural relationship.

Return for Risk

AMCPX vs. VIGIX — Risk / Return Rank

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

AMCPX

AMCPX Risk / Return Rank: 27
AMCPX Sharpe Ratio Rank: 30
AMCPX Sortino Ratio Rank: 28
AMCPX Omega Ratio Rank: 30
AMCPX Calmar Ratio Rank: 19
AMCPX Martin Ratio Rank: 27

VIGIX

VIGIX Risk / Return Rank: 34
VIGIX Sharpe Ratio Rank: 43
VIGIX Sortino Ratio Rank: 38
VIGIX Omega Ratio Rank: 39
VIGIX Calmar Ratio Rank: 25
VIGIX Martin Ratio Rank: 27

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.

AMCPX vs. VIGIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Funds AMCAP Fund Class A (AMCPX) and Vanguard Growth Index Fund Institutional Shares (VIGIX). 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.

	AMCPX	VIGIX	Difference
Sharpe ratio: Return per unit of total volatility	1.56	1.92	-0.36
Sortino ratio: Return per unit of downside risk	2.19	2.59	-0.41
Omega ratio: Gain probability vs. loss probability	1.28	1.33	-0.05
Calmar ratio: Return relative to maximum drawdown	1.60	1.85	-0.24
Martin ratio: Return relative to average drawdown	6.51	6.49	+0.01
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

AMCPX vs. VIGIX - Sharpe Ratio Comparison

The current AMCPX Sharpe Ratio is 1.56, which is comparable to the VIGIX Sharpe Ratio of 1.92. The chart below compares the historical Sharpe Ratios of AMCPX and VIGIX, 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

	AMCPX	VIGIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.56	1.92	-0.36
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.49	0.71	-0.22
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.66	0.86	-0.19
Sharpe Ratio (All Time) Calculated using the full available price history	0.59	0.47	+0.12

Drawdowns

AMCPX vs. VIGIX - Drawdown Comparison

The maximum AMCPX drawdown since its inception was -62.37%, which is greater than VIGIX's maximum drawdown of -56.95%. Use the drawdown chart below to compare losses from any high point for AMCPX and VIGIX.

Drawdown Indicators

	AMCPX	VIGIX	Difference
Max Drawdown Largest peak-to-trough decline	-62.37%	-56.95%	-5.42%
Max Drawdown (1Y) Largest decline over 1 year	-14.18%	-16.51%	+2.33%
Max Drawdown (3Y) Largest decline over 3 years	-19.71%	-23.03%	+3.32%
Max Drawdown (5Y) Largest decline over 5 years	-36.90%	-35.62%	-1.28%
Max Drawdown (10Y) Largest decline over 10 years	-36.90%	-35.62%	-1.28%
Current Drawdown Current decline from peak	-0.77%	-0.28%	-0.49%
Average Drawdown Average peak-to-trough decline	-9.58%	-16.28%	+6.70%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.49%	4.68%	-1.19%

Volatility

AMCPX vs. VIGIX - Volatility Comparison

American Funds AMCAP Fund Class A (AMCPX) and Vanguard Growth Index Fund Institutional Shares (VIGIX) have volatilities of 3.57% and 3.62%, 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

	AMCPX	VIGIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.57%	3.62%	-0.05%
Volatility (6M) Calculated over the trailing 6-month period	11.42%	12.10%	-0.68%
Volatility (1Y) Calculated over the trailing 1-year period	14.56%	15.87%	-1.31%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	19.24%	22.35%	-3.11%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.72%	21.59%	-2.87%

AMCPX vs. VIGIX - Expense Ratio Comparison

AMCPX has a 0.65% expense ratio, which is higher than VIGIX's 0.04% expense ratio.

Dividends

AMCPX vs. VIGIX - Dividend Comparison

AMCPX's dividend yield for the trailing twelve months is around 8.21%, more than VIGIX's 0.37% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AMCPX American Funds AMCAP Fund Class A	8.21%	8.73%	8.19%	3.26%	7.54%	3.43%	3.88%	4.90%	7.84%	5.37%	3.81%	8.86%
VIGIX Vanguard Growth Index Fund Institutional Shares	0.37%	0.41%	0.47%	0.58%	0.70%	0.48%	0.66%	0.95%	1.32%	1.15%	1.40%	1.31%

Frequently Asked Questions

Can I hold both AMCPX and VIGIX in my portfolio?

With a correlation of 0.93, AMCPX and VIGIX 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, AMCPX or VIGIX?

VIGIX has higher volatility (3.62%) compared to AMCPX (3.57%). In terms of maximum drawdown, AMCPX dropped -62.37% vs VIGIX's -56.95%.

Which has better risk-adjusted returns?

VIGIX currently has the higher Sharpe Ratio (1.92 vs 1.56), 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.