AMFFX vs. OAKMX

Last updated Jun 24, 2026

AMFFX (American Mutual Fund Class F-1) and OAKMX (Oakmark Fund Investor Class) are both Large Cap Value Equities funds. Both are actively managed. Over the past 10 years, AMFFX returned 11.35%/yr vs 13.78%/yr for OAKMX. Their correlation of 0.90 suggests significant overlap in exposure. AMFFX charges 0.64%/yr vs 0.89%/yr for OAKMX.

Performance

AMFFX vs. OAKMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Mutual Fund Class F-1 (AMFFX) and Oakmark Fund Investor Class (OAKMX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, AMFFX achieves a 6.66% return, which is significantly higher than OAKMX's -2.01% return. Over the past 10 years, AMFFX has underperformed OAKMX with an annualized return of 11.35%, while OAKMX has yielded a comparatively higher 13.78% annualized return.

AMFFX

• 1D: -0.14%
• 1M: 0.34%
• YTD: 6.66%
• 6M: 6.13%
• 1Y: 16.24%
• 3Y*: 15.31%
• 5Y*: 10.60%
• 10Y*: 11.35%

OAKMX

• 1D: 0.00%
• 1M: -1.03%
• YTD: -2.01%
• 6M: -2.54%
• 1Y: 8.70%
• 3Y*: 14.33%
• 5Y*: 9.77%
• 10Y*: 13.78%

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

AMFFX vs. OAKMX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
AMFFX American Mutual Fund Class F-1	6.66%	15.99%	14.87%	9.36%	-4.54%	25.04%	4.73%	21.48%	-2.37%	17.44%
OAKMX Oakmark Fund Investor Class	-2.01%	14.13%	16.02%	30.92%	-13.38%	34.85%	12.90%	27.14%	-12.76%	21.12%

Correlation

The correlation between AMFFX and OAKMX is 0.68, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.68
Correlation (3Y) Calculated over the trailing 3-year period	0.78
Correlation (5Y) Calculated over the trailing 5-year period	0.83
Correlation (10Y) Calculated over the trailing 10-year period	0.83
Correlation (All Time) Calculated using the full available price history since Mar 15, 2001	0.90

Over the past year, the correlation between AMFFX and OAKMX has dropped to 0.68 - well below their long-term average of 0.90, suggesting their price drivers have been diverging.

Return for Risk

AMFFX vs. OAKMX — Risk / Return Rank

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

AMFFX

AMFFX Risk / Return Rank: 41
AMFFX Sharpe Ratio Rank: 43
AMFFX Sortino Ratio Rank: 41
AMFFX Omega Ratio Rank: 41
AMFFX Calmar Ratio Rank: 37
AMFFX Martin Ratio Rank: 43

OAKMX

OAKMX Risk / Return Rank: 11
OAKMX Sharpe Ratio Rank: 9
OAKMX Sortino Ratio Rank: 9
OAKMX Omega Ratio Rank: 8
OAKMX Calmar Ratio Rank: 15
OAKMX Martin Ratio Rank: 12

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.

AMFFX vs. OAKMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Mutual Fund Class F-1 (AMFFX) and Oakmark Fund Investor Class (OAKMX). 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.

	AMFFX	OAKMX	Difference
Sharpe ratio: Return per unit of total volatility	1.78	0.68	+1.09
Sortino ratio: Return per unit of downside risk	2.49	1.07	+1.43
Omega ratio: Gain probability vs. loss probability	1.32	1.13	+0.19
Calmar ratio: Return relative to maximum drawdown	2.18	1.29	+0.88
Martin ratio: Return relative to average drawdown	8.73	3.17	+5.55

AMFFX vs. OAKMX - Sharpe Ratio Comparison

The current AMFFX Sharpe Ratio is 1.78, which is higher than the OAKMX Sharpe Ratio of 0.68. The chart below compares the historical Sharpe Ratios of AMFFX and OAKMX, 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

AMFFX vs. OAKMX - Drawdown Comparison

The maximum AMFFX drawdown since its inception was -48.76%, smaller than the maximum OAKMX drawdown of -56.19%. Use the drawdown chart below to compare losses from any high point for AMFFX and OAKMX.

Drawdown Indicators

	AMFFX	OAKMX	Difference
Max Drawdown Largest peak-to-trough decline	-48.76%	-56.19%	+7.43%
Max Drawdown (1Y) Largest decline over 1 year	-7.93%	-6.98%	-0.95%
Max Drawdown (3Y) Largest decline over 3 years	-12.95%	-17.05%	+4.10%
Max Drawdown (5Y) Largest decline over 5 years	-15.32%	-23.68%	+8.36%
Max Drawdown (10Y) Largest decline over 10 years	-29.83%	-41.43%	+11.60%
Current Drawdown Current decline from peak	-0.77%	-4.52%	+3.75%
Average Drawdown Average peak-to-trough decline	-5.72%	-6.39%	+0.67%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.97%	2.84%	-0.87%

Volatility

AMFFX vs. OAKMX - Volatility Comparison

The current volatility for American Mutual Fund Class F-1 (AMFFX) is 2.75%, while Oakmark Fund Investor Class (OAKMX) has a volatility of 3.77%. This indicates that AMFFX experiences smaller price fluctuations and is considered to be less risky than OAKMX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	AMFFX	OAKMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.75%	3.77%	-1.02%
Volatility (6M) Calculated over the trailing 6-month period	7.47%	9.44%	-1.97%
Volatility (1Y) Calculated over the trailing 1-year period	9.72%	13.20%	-3.48%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	12.51%	18.28%	-5.77%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	14.13%	20.41%	-6.28%

AMFFX vs. OAKMX - Expense Ratio Comparison

AMFFX has a 0.64% expense ratio, which is lower than OAKMX's 0.89% expense ratio.

Dividends

AMFFX vs. OAKMX - Dividend Comparison

AMFFX's dividend yield for the trailing twelve months is around 7.11%, more than OAKMX's 0.94% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AMFFX American Mutual Fund Class F-1	7.11%	7.53%	6.26%	3.72%	4.84%	4.73%	1.95%	4.56%	6.38%	5.89%	4.78%	6.48%
OAKMX Oakmark Fund Investor Class	0.94%	0.92%	1.12%	1.02%	0.92%	1.94%	0.17%	8.33%	8.13%	4.06%	2.58%	1.43%

Frequently Asked Questions

Can I hold both AMFFX and OAKMX in my portfolio?

AMFFX and OAKMX have a correlation of 0.68, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, AMFFX or OAKMX?

OAKMX has higher volatility (3.77%) compared to AMFFX (2.75%). In terms of maximum drawdown, AMFFX dropped -48.76% vs OAKMX's -56.19%.

Which has better risk-adjusted returns?

AMFFX currently has the higher Sharpe Ratio (1.78 vs 0.68), 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.