RFNGX vs. AGTHX

Last updated Jun 24, 2026

RFNGX (American Funds Fundamental Investors Fund Class R6) and AGTHX (American Funds The Growth Fund of America Class A) are both Large Cap Growth Equities funds from Capital Group. Both are actively managed. Over the past 10 years, RFNGX returned 15.45%/yr vs 16.28%/yr for AGTHX. With a 0.96 correlation, they move nearly in lockstep. RFNGX charges 0.28%/yr vs 0.59%/yr for AGTHX.

Performance

RFNGX vs. AGTHX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Funds Fundamental Investors Fund Class R6 (RFNGX) and American Funds The Growth Fund of America Class A (AGTHX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, RFNGX achieves a 14.40% return, which is significantly higher than AGTHX's 8.72% return. Over the past 10 years, RFNGX has underperformed AGTHX with an annualized return of 15.45%, while AGTHX has yielded a comparatively higher 16.28% annualized return.

RFNGX

• 1D: -0.54%
• 1M: 1.93%
• YTD: 14.40%
• 6M: 14.09%
• 1Y: 31.89%
• 3Y*: 25.52%
• 5Y*: 14.92%
• 10Y*: 15.45%

AGTHX

• 1D: -0.52%
• 1M: 1.96%
• YTD: 8.72%
• 6M: 7.83%
• 1Y: 22.79%
• 3Y*: 23.94%
• 5Y*: 11.48%
• 10Y*: 16.28%

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

RFNGX vs. AGTHX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
RFNGX American Funds Fundamental Investors Fund Class R6	14.40%	24.58%	22.77%	26.25%	-16.38%	22.83%	13.72%	27.48%	-7.09%	23.15%
AGTHX American Funds The Growth Fund of America Class A	8.72%	19.73%	28.02%	37.22%	-30.75%	19.32%	37.83%	28.16%	-3.15%	26.14%

Correlation

The correlation between RFNGX and AGTHX is 0.95 - 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	0.95
Correlation (3Y) Calculated over the trailing 3-year period	0.96
Correlation (5Y) Calculated over the trailing 5-year period	0.96
Correlation (10Y) Calculated over the trailing 10-year period	0.95
Correlation (All Time) Calculated using the full available price history since Jan 4, 2010	0.96

The correlation between RFNGX and AGTHX has been stable across timeframes, ranging from 0.95 to 0.96 - a consistent structural relationship.

Return for Risk

RFNGX vs. AGTHX — Risk / Return Rank

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

RFNGX

RFNGX Risk / Return Rank: 70
RFNGX Sharpe Ratio Rank: 71
RFNGX Sortino Ratio Rank: 63
RFNGX Omega Ratio Rank: 64
RFNGX Calmar Ratio Rank: 71
RFNGX Martin Ratio Rank: 81

AGTHX

AGTHX Risk / Return Rank: 29
AGTHX Sharpe Ratio Rank: 30
AGTHX Sortino Ratio Rank: 28
AGTHX Omega Ratio Rank: 31
AGTHX Calmar Ratio Rank: 25
AGTHX Martin Ratio Rank: 31

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.

RFNGX vs. AGTHX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Funds Fundamental Investors Fund Class R6 (RFNGX) and American Funds The Growth Fund of America Class A (AGTHX). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	RFNGX	AGTHX	Difference
Sharpe ratio: Return per unit of total volatility	2.25	1.48	+0.77
Sortino ratio: Return per unit of downside risk	3.03	2.05	+0.98
Omega ratio: Gain probability vs. loss probability	1.40	1.27	+0.13
Calmar ratio: Return relative to maximum drawdown	3.10	1.75	+1.35
Martin ratio: Return relative to average drawdown	13.98	6.69	+7.28

RFNGX vs. AGTHX - Sharpe Ratio Comparison

The current RFNGX Sharpe Ratio is 2.25, which is higher than the AGTHX Sharpe Ratio of 1.48. The chart below compares the historical Sharpe Ratios of RFNGX and AGTHX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

RFNGX vs. AGTHX - Drawdown Comparison

The maximum RFNGX drawdown since its inception was -33.90%, smaller than the maximum AGTHX drawdown of -51.91%. Use the drawdown chart below to compare losses from any high point for RFNGX and AGTHX.

Drawdown Indicators

	RFNGX	AGTHX	Difference
Max Drawdown Largest peak-to-trough decline	-33.90%	-51.91%	+18.01%
Max Drawdown (1Y) Largest decline over 1 year	-10.62%	-13.76%	+3.14%
Max Drawdown (3Y) Largest decline over 3 years	-17.92%	-21.57%	+3.65%
Max Drawdown (5Y) Largest decline over 5 years	-24.88%	-36.38%	+11.50%
Max Drawdown (10Y) Largest decline over 10 years	-33.90%	-36.38%	+2.48%
Current Drawdown Current decline from peak	-0.76%	-1.56%	+0.80%
Average Drawdown Average peak-to-trough decline	-4.01%	-9.19%	+5.18%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.35%	3.60%	-1.25%

Volatility

RFNGX vs. AGTHX - Volatility Comparison

The current volatility for American Funds Fundamental Investors Fund Class R6 (RFNGX) is 5.60%, while American Funds The Growth Fund of America Class A (AGTHX) has a volatility of 6.79%. This indicates that RFNGX experiences smaller price fluctuations and is considered to be less risky than AGTHX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	RFNGX	AGTHX	Difference
Volatility (1M) Calculated over the trailing 1-month period	5.60%	6.79%	-1.19%
Volatility (6M) Calculated over the trailing 6-month period	11.71%	13.02%	-1.31%
Volatility (1Y) Calculated over the trailing 1-year period	14.65%	16.31%	-1.66%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.95%	20.43%	-3.48%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	17.80%	19.78%	-1.98%

RFNGX vs. AGTHX - Expense Ratio Comparison

RFNGX has a 0.28% expense ratio, which is lower than AGTHX's 0.59% expense ratio.

Dividends

RFNGX vs. AGTHX - Dividend Comparison

RFNGX's dividend yield for the trailing twelve months is around 7.57%, less than AGTHX's 9.84% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AGTHX American Funds The Growth Fund of America Class A	9.84%	10.69%	8.99%	7.40%	4.05%	8.18%	4.30%	7.15%	11.99%	7.03%	6.61%	8.87%
RFNGX American Funds Fundamental Investors Fund Class R6	7.57%	8.82%	8.91%	6.10%	5.33%	11.29%	1.77%	7.21%	10.67%	7.56%	5.01%	6.01%

Frequently Asked Questions

Can I hold both RFNGX and AGTHX in my portfolio?

With a correlation of 0.95, RFNGX and AGTHX 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, RFNGX or AGTHX?

AGTHX has higher volatility (6.79%) compared to RFNGX (5.60%). In terms of maximum drawdown, RFNGX dropped -33.90% vs AGTHX's -51.91%.

Which has better risk-adjusted returns?

RFNGX currently has the higher Sharpe Ratio (2.25 vs 1.48), 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.