TWCIX vs. ONERX

Last updated Jun 4, 2026

TWCIX (American Century Select Fund) and ONERX (One Rock Fund) are both Large Cap Growth Equities funds. Over the past 5 years, TWCIX returned 13.60%/yr vs 34.52%/yr for ONERX. Their correlation of 0.82 suggests significant overlap in exposure. TWCIX charges 0.94%/yr vs 1.75%/yr for ONERX.

Performance

TWCIX vs. ONERX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century Select Fund (TWCIX) and One Rock Fund (ONERX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TWCIX achieves a 8.87% return, which is significantly lower than ONERX's 66.81% return.

TWCIX

• 1D: -0.34%
• 1M: 5.18%
• YTD: 8.87%
• 6M: 8.46%
• 1Y: 28.26%
• 3Y*: 21.44%
• 5Y*: 13.60%
• 10Y*: 16.94%

ONERX

• 1D: 3.19%
• 1M: 23.36%
• YTD: 66.81%
• 6M: 66.34%
• 1Y: 129.67%
• 3Y*: 57.09%
• 5Y*: 34.52%
• 10Y*: —

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

TWCIX vs. ONERX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020
TWCIX American Century Select Fund	8.87%	16.30%	26.15%	39.93%	-28.82%	25.47%	49.93%
ONERX One Rock Fund	66.81%	49.37%	21.76%	72.41%	-42.06%	45.70%	104.46%

Correlation

The correlation between TWCIX and ONERX is 0.72, 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	0.72
Correlation (3Y) Calculated over the trailing 3-year period	0.80
Correlation (5Y) Calculated over the trailing 5-year period	0.83
Correlation (All Time) Calculated using the full available price history since Mar 16, 2020	0.82

The correlation between TWCIX and ONERX shifts across timeframes, from 0.72 (1 year) to 0.83 (5 years), reflecting how their relationship changes across market environments.

Return for Risk

TWCIX vs. ONERX — Risk / Return Rank

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

TWCIX

TWCIX Risk / Return Rank: 34
TWCIX Sharpe Ratio Rank: 40
TWCIX Sortino Ratio Rank: 35
TWCIX Omega Ratio Rank: 36
TWCIX Calmar Ratio Rank: 28
TWCIX Martin Ratio Rank: 33

ONERX

ONERX Risk / Return Rank: 88
ONERX Sharpe Ratio Rank: 97
ONERX Sortino Ratio Rank: 73
ONERX Omega Ratio Rank: 77
ONERX Calmar Ratio Rank: 98
ONERX Martin Ratio Rank: 97

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.

TWCIX vs. ONERX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century Select Fund (TWCIX) and One Rock Fund (ONERX). 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.

	TWCIX	ONERX	Difference
Sharpe ratio: Return per unit of total volatility	1.84	3.59	-1.75
Sortino ratio: Return per unit of downside risk	2.48	3.57	-1.09
Omega ratio: Gain probability vs. loss probability	1.32	1.50	-0.18
Calmar ratio: Return relative to maximum drawdown	1.99	7.71	-5.72
Martin ratio: Return relative to average drawdown	7.44	27.26	-19.82
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

TWCIX vs. ONERX - Sharpe Ratio Comparison

The current TWCIX Sharpe Ratio is 1.84, which is lower than the ONERX Sharpe Ratio of 3.59. The chart below compares the historical Sharpe Ratios of TWCIX and ONERX, 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

	TWCIX	ONERX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.84	3.59	-1.75
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.64	0.89	-0.25
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.81	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.59	1.11	-0.52

Drawdowns

TWCIX vs. ONERX - Drawdown Comparison

The maximum TWCIX drawdown since its inception was -57.31%, which is greater than ONERX's maximum drawdown of -47.44%. Use the drawdown chart below to compare losses from any high point for TWCIX and ONERX.

Drawdown Indicators

	TWCIX	ONERX	Difference
Max Drawdown Largest peak-to-trough decline	-57.31%	-47.44%	-9.87%
Max Drawdown (1Y) Largest decline over 1 year	-14.66%	-17.63%	+2.97%
Max Drawdown (3Y) Largest decline over 3 years	-23.88%	-47.44%	+23.56%
Max Drawdown (5Y) Largest decline over 5 years	-31.24%	-47.44%	+16.20%
Max Drawdown (10Y) Largest decline over 10 years	-31.24%	—	—
Current Drawdown Current decline from peak	-0.34%	0.00%	-0.34%
Average Drawdown Average peak-to-trough decline	-12.39%	-13.80%	+1.41%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.91%	4.98%	-1.07%

Volatility

TWCIX vs. ONERX - Volatility Comparison

The current volatility for American Century Select Fund (TWCIX) is 3.60%, while One Rock Fund (ONERX) has a volatility of 11.93%. This indicates that TWCIX experiences smaller price fluctuations and is considered to be less risky than ONERX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TWCIX	ONERX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.60%	11.93%	-8.33%
Volatility (6M) Calculated over the trailing 6-month period	12.03%	29.84%	-17.81%
Volatility (1Y) Calculated over the trailing 1-year period	15.87%	37.90%	-22.03%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	21.48%	39.12%	-17.64%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.03%	38.21%	-17.18%

TWCIX vs. ONERX - Expense Ratio Comparison

TWCIX has a 0.94% expense ratio, which is lower than ONERX's 1.75% expense ratio.

Dividends

TWCIX vs. ONERX - Dividend Comparison

TWCIX's dividend yield for the trailing twelve months is around 9.22%, less than ONERX's 14.46% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
ONERX One Rock Fund	14.46%	24.12%	0.00%	0.00%	10.57%	28.88%	18.66%	0.00%	0.00%	0.00%	0.00%	0.00%
TWCIX American Century Select Fund	9.22%	10.04%	3.67%	5.21%	10.36%	8.25%	6.26%	5.42%	9.05%	6.30%	3.43%	6.16%

Frequently Asked Questions

Can I hold both TWCIX and ONERX in my portfolio?

TWCIX and ONERX have a correlation of 0.72, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, TWCIX or ONERX?

ONERX has higher volatility (11.93%) compared to TWCIX (3.60%). In terms of maximum drawdown, TWCIX dropped -57.31% vs ONERX's -47.44%.

Which has better risk-adjusted returns?

ONERX currently has the higher Sharpe Ratio (3.59 vs 1.84), 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.