CPTNX vs. TWCIX

Last updated Apr 1, 2026

Compare and contrast key facts about American Century Government Bond Fund (CPTNX) and American Century Select Fund (TWCIX).

CPTNX is managed by American Century. It was launched on May 15, 1980. TWCIX is managed by American Century. It was launched on Jun 30, 1971.

Performance

CPTNX vs. TWCIX - Performance Comparison

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

CPTNX vs. TWCIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
CPTNX American Century Government Bond Fund	-0.43%	7.26%	0.32%	3.51%	-13.10%	-1.24%	6.71%	6.16%	0.57%	2.15%
TWCIX American Century Select Fund	-12.29%	16.30%	26.15%	39.93%	-28.82%	25.47%	33.99%	36.30%	-3.54%	28.90%

Returns By Period

In the year-to-date period, CPTNX achieves a -0.43% return, which is significantly higher than TWCIX's -12.29% return. Over the past 10 years, CPTNX has underperformed TWCIX with an annualized return of 0.87%, while TWCIX has yielded a comparatively higher 14.46% annualized return.

CPTNX

• 1D: 0.54%
• 1M: -2.29%
• YTD: -0.43%
• 6M: 0.79%
• 1Y: 3.89%
• 3Y*: 2.51%
• 5Y*: -0.51%
• 10Y*: 0.87%

TWCIX

• 1D: -0.45%
• 1M: -8.75%
• YTD: -12.29%
• 6M: -10.54%
• 1Y: 13.57%
• 3Y*: 15.91%
• 5Y*: 9.81%
• 10Y*: 14.46%

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

CPTNX vs. TWCIX - Expense Ratio Comparison

CPTNX has a 0.47% expense ratio, which is lower than TWCIX's 0.94% expense ratio.

TWCIX

American Century Select Fund

CPTNX

American Century Government Bond Fund

Return for Risk

CPTNX vs. TWCIX — Risk / Return Rank

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

CPTNX

CPTNX Risk / Return Rank: 50
CPTNX Sharpe Ratio Rank: 49
CPTNX Sortino Ratio Rank: 48
CPTNX Omega Ratio Rank: 33
CPTNX Calmar Ratio Rank: 72
CPTNX Martin Ratio Rank: 46

TWCIX

TWCIX Risk / Return Rank: 27
TWCIX Sharpe Ratio Rank: 26
TWCIX Sortino Ratio Rank: 29
TWCIX Omega Ratio Rank: 28
TWCIX Calmar Ratio Rank: 26
TWCIX Martin Ratio Rank: 25

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.

CPTNX vs. TWCIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century Government Bond Fund (CPTNX) and American Century Select Fund (TWCIX). 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.

	CPTNX	TWCIX	Difference
Sharpe ratio Return per unit of total volatility	0.95	0.61	+0.34
Sortino ratio Return per unit of downside risk	1.37	1.03	+0.34
Omega ratio Gain probability vs. loss probability	1.17	1.14	+0.02
Calmar ratio Return relative to maximum drawdown	1.67	0.74	+0.94
Martin ratio Return relative to average drawdown	4.60	2.69	+1.91
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CPTNX vs. TWCIX - Sharpe Ratio Comparison

The current CPTNX Sharpe Ratio is 0.95, which is higher than the TWCIX Sharpe Ratio of 0.61. The chart below compares the historical Sharpe Ratios of CPTNX and TWCIX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	CPTNX	TWCIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.95	0.61	+0.34
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.08	0.46	-0.54
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.18	0.69	-0.52
Sharpe Ratio (All Time) Calculated using the full available price history	1.15	0.57	+0.58

Correlation

The correlation between CPTNX and TWCIX is -0.02. This indicates that the assets' prices tend to move in opposite directions. Negative correlation can be particularly beneficial for diversification and risk management, as one asset may offset the losses of the other during market fluctuations.

Dividends

CPTNX vs. TWCIX - Dividend Comparison

CPTNX's dividend yield for the trailing twelve months is around 3.73%, less than TWCIX's 11.44% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
CPTNX American Century Government Bond Fund	3.73%	4.07%	4.22%	3.72%	1.84%	2.10%	2.09%	2.48%	2.49%	2.14%	2.28%	1.69%
TWCIX American Century Select Fund	11.44%	10.04%	3.67%	5.21%	10.36%	8.25%	6.26%	5.42%	9.05%	6.30%	3.43%	6.16%

Drawdowns

CPTNX vs. TWCIX - Drawdown Comparison

The maximum CPTNX drawdown since its inception was -19.73%, smaller than the maximum TWCIX drawdown of -57.31%. Use the drawdown chart below to compare losses from any high point for CPTNX and TWCIX.

Drawdown Indicators

	CPTNX	TWCIX	Difference
Max Drawdown Largest peak-to-trough decline	-19.73%	-57.31%	+37.58%
Max Drawdown (1Y) Largest decline over 1 year	-2.95%	-14.66%	+11.71%
Max Drawdown (5Y) Largest decline over 5 years	-19.15%	-31.24%	+12.09%
Max Drawdown (10Y) Largest decline over 10 years	-19.73%	-31.24%	+11.51%
Current Drawdown Current decline from peak	-5.51%	-14.66%	+9.15%
Average Drawdown Average peak-to-trough decline	-2.28%	-12.42%	+10.14%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.07%	4.01%	-2.94%

Volatility

CPTNX vs. TWCIX - Volatility Comparison

The current volatility for American Century Government Bond Fund (CPTNX) is 1.62%, while American Century Select Fund (TWCIX) has a volatility of 5.75%. This indicates that CPTNX experiences smaller price fluctuations and is considered to be less risky than TWCIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CPTNX	TWCIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.62%	5.75%	-4.13%
Volatility (6M) Calculated over the trailing 6-month period	2.66%	12.15%	-9.49%
Volatility (1Y) Calculated over the trailing 1-year period	4.63%	22.70%	-18.07%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	6.24%	21.43%	-15.19%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.96%	20.94%	-15.98%