TWCUX vs. ACFOX

Last updated Jun 5, 2026

TWCUX (American Century Ultra Fund) and ACFOX (American Century Investments Focused Dynamic Growth Fund) are both Large Cap Growth Equities funds from American Century. Over the past 10 years, TWCUX returned 18.10%/yr vs 19.35%/yr for ACFOX. Their correlation of 0.93 suggests significant overlap in exposure. TWCUX charges 0.93%/yr vs 0.85%/yr for ACFOX.

Performance

TWCUX vs. ACFOX - Performance Comparison

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

Returns By Period

In the year-to-date period, TWCUX achieves a 7.91% return, which is significantly higher than ACFOX's 7.27% return. Over the past 10 years, TWCUX has underperformed ACFOX with an annualized return of 18.10%, while ACFOX has yielded a comparatively higher 19.35% annualized return.

TWCUX

• 1D: -1.62%
• 1M: 3.99%
• YTD: 7.91%
• 6M: 6.18%
• 1Y: 22.99%
• 3Y*: 21.28%
• 5Y*: 12.30%
• 10Y*: 18.10%

ACFOX

• 1D: -1.84%
• 1M: 4.32%
• YTD: 7.27%
• 6M: 8.09%
• 1Y: 30.11%
• 3Y*: 27.50%
• 5Y*: 11.03%
• 10Y*: 19.35%

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

TWCUX vs. ACFOX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
TWCUX American Century Ultra Fund	7.91%	12.66%	29.54%	43.36%	-32.38%	23.47%	49.79%	34.60%	0.70%	31.65%
ACFOX American Century Investments Focused Dynamic Growth Fund	7.27%	20.51%	43.30%	35.66%	-36.32%	7.08%	73.31%	32.30%	6.51%	34.55%

Correlation

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

Return for Risk

TWCUX vs. ACFOX — Risk / Return Rank

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

TWCUX

TWCUX Risk / Return Rank: 22
TWCUX Sharpe Ratio Rank: 25
TWCUX Sortino Ratio Rank: 23
TWCUX Omega Ratio Rank: 22
TWCUX Calmar Ratio Rank: 18
TWCUX Martin Ratio Rank: 20

ACFOX

ACFOX Risk / Return Rank: 29
ACFOX Sharpe Ratio Rank: 32
ACFOX Sortino Ratio Rank: 28
ACFOX Omega Ratio Rank: 29
ACFOX Calmar Ratio Rank: 26
ACFOX Martin Ratio Rank: 28

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.

TWCUX vs. ACFOX - Risk-Adjusted Trends Comparison

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

	TWCUX	ACFOX	Difference
Sharpe ratio: Return per unit of total volatility	1.45	1.63	-0.19
Sortino ratio: Return per unit of downside risk	2.01	2.23	-0.22
Omega ratio: Gain probability vs. loss probability	1.25	1.28	-0.03
Calmar ratio: Return relative to maximum drawdown	1.51	1.87	-0.36
Martin ratio: Return relative to average drawdown	5.28	6.58	-1.30
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

TWCUX vs. ACFOX - Sharpe Ratio Comparison

The current TWCUX Sharpe Ratio is 1.45, which is comparable to the ACFOX Sharpe Ratio of 1.63. The chart below compares the historical Sharpe Ratios of TWCUX and ACFOX, 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

	TWCUX	ACFOX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.45	1.63	-0.19
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.55	0.44	+0.11
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.82	0.82	+0.01
Sharpe Ratio (All Time) Calculated using the full available price history	0.53	0.58	-0.05

Drawdowns

TWCUX vs. ACFOX - Drawdown Comparison

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

Drawdown Indicators

	TWCUX	ACFOX	Difference
Max Drawdown Largest peak-to-trough decline	-62.11%	-58.92%	-3.19%
Max Drawdown (1Y) Largest decline over 1 year	-15.72%	-16.52%	+0.80%
Max Drawdown (3Y) Largest decline over 3 years	-24.86%	-27.03%	+2.17%
Max Drawdown (5Y) Largest decline over 5 years	-35.23%	-43.77%	+8.54%
Max Drawdown (10Y) Largest decline over 10 years	-35.23%	-43.77%	+8.54%
Current Drawdown Current decline from peak	-2.00%	-2.88%	+0.88%
Average Drawdown Average peak-to-trough decline	-16.81%	-14.71%	-2.10%
Ulcer Index Depth and duration of drawdowns from previous peaks	4.48%	4.68%	-0.20%

Volatility

TWCUX vs. ACFOX - Volatility Comparison

The current volatility for American Century Ultra Fund (TWCUX) is 4.24%, while American Century Investments Focused Dynamic Growth Fund (ACFOX) has a volatility of 5.59%. This indicates that TWCUX experiences smaller price fluctuations and is considered to be less risky than ACFOX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TWCUX	ACFOX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.24%	5.59%	-1.35%
Volatility (6M) Calculated over the trailing 6-month period	12.44%	14.68%	-2.24%
Volatility (1Y) Calculated over the trailing 1-year period	16.39%	18.89%	-2.50%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	22.56%	25.28%	-2.72%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	22.08%	23.81%	-1.73%

TWCUX vs. ACFOX - Expense Ratio Comparison

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

Dividends

TWCUX vs. ACFOX - Dividend Comparison

TWCUX's dividend yield for the trailing twelve months is around 10.73%, more than ACFOX's 7.04% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ACFOX American Century Investments Focused Dynamic Growth Fund	7.04%	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	10.73%	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 TWCUX and ACFOX in my portfolio?

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

ACFOX has higher volatility (5.59%) compared to TWCUX (4.24%). In terms of maximum drawdown, TWCUX dropped -62.11% vs ACFOX's -58.92%.

Which has better risk-adjusted returns?

ACFOX currently has the higher Sharpe Ratio (1.63 vs 1.45), 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.