ACFOX vs. TWCUX

Last updated Jun 4, 2026

ACFOX (American Century Investments Focused Dynamic Growth Fund) and TWCUX (American Century Ultra Fund) are both Large Cap Growth Equities funds from American Century. Over the past 10 years, ACFOX returned 19.58%/yr vs 18.29%/yr for TWCUX. Their correlation of 0.93 suggests significant overlap in exposure. ACFOX charges 0.85%/yr vs 0.93%/yr for TWCUX.

Performance

ACFOX vs. TWCUX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century Investments Focused Dynamic Growth Fund (ACFOX) and American Century Ultra Fund (TWCUX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both investments are quite close, with ACFOX having a 9.28% return and TWCUX slightly higher at 9.68%. Over the past 10 years, ACFOX has outperformed TWCUX with an annualized return of 19.58%, while TWCUX has yielded a comparatively lower 18.29% annualized return.

ACFOX

• 1D: -1.06%
• 1M: 5.78%
• YTD: 9.28%
• 6M: 10.92%
• 1Y: 33.16%
• 3Y*: 28.29%
• 5Y*: 11.86%
• 10Y*: 19.58%

TWCUX

• 1D: -0.39%
• 1M: 6.24%
• YTD: 9.68%
• 6M: 8.02%
• 1Y: 25.64%
• 3Y*: 21.95%
• 5Y*: 13.04%
• 10Y*: 18.29%

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

ACFOX vs. TWCUX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
ACFOX American Century Investments Focused Dynamic Growth Fund	9.28%	20.51%	43.30%	35.66%	-36.32%	7.08%	73.31%	32.30%	6.51%	34.55%
TWCUX American Century Ultra Fund	9.68%	12.66%	29.54%	43.36%	-32.38%	23.47%	49.79%	34.60%	0.70%	31.65%

Correlation

The correlation between ACFOX and TWCUX is 0.95, 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	0.95
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 Jun 1, 2006	0.93

The correlation between ACFOX and TWCUX has been stable across timeframes, ranging from 0.93 to 0.96 - a consistent structural relationship.

Return for Risk

ACFOX vs. TWCUX — Risk / Return Rank

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

ACFOX

ACFOX Risk / Return Rank: 34
ACFOX Sharpe Ratio Rank: 38
ACFOX Sortino Ratio Rank: 34
ACFOX Omega Ratio Rank: 34
ACFOX Calmar Ratio Rank: 30
ACFOX Martin Ratio Rank: 31

TWCUX

TWCUX Risk / Return Rank: 27
TWCUX Sharpe Ratio Rank: 32
TWCUX Sortino Ratio Rank: 29
TWCUX Omega Ratio Rank: 29
TWCUX Calmar Ratio Rank: 21
TWCUX Martin Ratio Rank: 23

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.

ACFOX vs. TWCUX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century Investments Focused Dynamic Growth Fund (ACFOX) and American Century Ultra Fund (TWCUX). 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.

	ACFOX	TWCUX	Difference
Sharpe ratio: Return per unit of total volatility	1.80	1.62	+0.18
Sortino ratio: Return per unit of downside risk	2.43	2.23	+0.20
Omega ratio: Gain probability vs. loss probability	1.31	1.28	+0.03
Calmar ratio: Return relative to maximum drawdown	2.05	1.68	+0.37
Martin ratio: Return relative to average drawdown	7.24	5.89	+1.34
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

ACFOX vs. TWCUX - Sharpe Ratio Comparison

The current ACFOX Sharpe Ratio is 1.80, which is comparable to the TWCUX Sharpe Ratio of 1.62. The chart below compares the historical Sharpe Ratios of ACFOX and TWCUX, 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

	ACFOX	TWCUX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.80	1.62	+0.18
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.47	0.58	-0.11
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.83	0.83	-0.01
Sharpe Ratio (All Time) Calculated using the full available price history	0.58	0.53	+0.05

Drawdowns

ACFOX vs. TWCUX - Drawdown Comparison

The maximum ACFOX drawdown since its inception was -58.92%, smaller than the maximum TWCUX drawdown of -62.11%. Use the drawdown chart below to compare losses from any high point for ACFOX and TWCUX.

Drawdown Indicators

	ACFOX	TWCUX	Difference
Max Drawdown Largest peak-to-trough decline	-58.92%	-62.11%	+3.19%
Max Drawdown (1Y) Largest decline over 1 year	-16.52%	-15.72%	-0.80%
Max Drawdown (3Y) Largest decline over 3 years	-27.03%	-24.86%	-2.17%
Max Drawdown (5Y) Largest decline over 5 years	-43.77%	-35.23%	-8.54%
Max Drawdown (10Y) Largest decline over 10 years	-43.77%	-35.23%	-8.54%
Current Drawdown Current decline from peak	-1.06%	-0.39%	-0.67%
Average Drawdown Average peak-to-trough decline	-14.71%	-16.81%	+2.10%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.67%	4.48%	+0.19%

Volatility

ACFOX vs. TWCUX - Volatility Comparison

American Century Investments Focused Dynamic Growth Fund (ACFOX) has a higher volatility of 5.17% compared to American Century Ultra Fund (TWCUX) at 3.78%. This indicates that ACFOX's price experiences larger fluctuations and is considered to be riskier than TWCUX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	ACFOX	TWCUX	Difference
Volatility (1M) Calculated over the trailing 1-month period	5.17%	3.78%	+1.39%
Volatility (6M) Calculated over the trailing 6-month period	14.56%	12.33%	+2.23%
Volatility (1Y) Calculated over the trailing 1-year period	18.80%	16.31%	+2.49%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	25.28%	22.56%	+2.72%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.81%	22.08%	+1.73%

ACFOX vs. TWCUX - Expense Ratio Comparison

ACFOX has a 0.85% expense ratio, which is lower than TWCUX's 0.93% expense ratio.

Dividends

ACFOX vs. TWCUX - Dividend Comparison

ACFOX's dividend yield for the trailing twelve months is around 6.91%, less than TWCUX's 10.55% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ACFOX American Century Investments Focused Dynamic Growth Fund	6.91%	7.56%	0.00%	0.00%	0.00%	2.48%	0.62%	0.00%	0.00%	0.00%	1.15%	1.33%
TWCUX American Century Ultra Fund	10.55%	11.57%	3.58%	6.09%	7.42%	6.78%	2.80%	4.27%	8.24%	5.85%	4.58%	5.21%

Frequently Asked Questions

Can I hold both ACFOX and TWCUX in my portfolio?

With a correlation of 0.95, ACFOX and TWCUX 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, ACFOX or TWCUX?

ACFOX has higher volatility (5.17%) compared to TWCUX (3.78%). In terms of maximum drawdown, ACFOX dropped -58.92% vs TWCUX's -62.11%.

Which has better risk-adjusted returns?

ACFOX currently has the higher Sharpe Ratio (1.80 vs 1.62), 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.