CMPGX vs. BGNMX

Last updated Jun 5, 2026

CMPGX (Principal Government & High Quality Bond Fund) and BGNMX (American Century Ginnie Mae Fund) are both Government Bonds funds. Over the past 10 years, CMPGX returned 0.58%/yr vs 0.87%/yr for BGNMX. Their correlation of 0.83 suggests significant overlap in exposure. CMPGX charges 0.78%/yr vs 0.55%/yr for BGNMX.

Performance

CMPGX vs. BGNMX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Principal Government & High Quality Bond Fund (CMPGX) and American Century Ginnie Mae Fund (BGNMX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, CMPGX achieves a 0.08% return, which is significantly lower than BGNMX's 0.62% return. Over the past 10 years, CMPGX has underperformed BGNMX with an annualized return of 0.58%, while BGNMX has yielded a comparatively higher 0.87% annualized return.

CMPGX

• 1D: -0.22%
• 1M: -0.01%
• YTD: 0.08%
• 6M: 0.28%
• 1Y: 5.16%
• 3Y*: 3.43%
• 5Y*: -0.57%
• 10Y*: 0.58%

BGNMX

• 1D: -0.11%
• 1M: -0.01%
• YTD: 0.62%
• 6M: 0.95%
• 1Y: 5.53%
• 3Y*: 3.76%
• 5Y*: -0.15%
• 10Y*: 0.87%

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

CMPGX vs. BGNMX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
CMPGX Principal Government & High Quality Bond Fund	0.08%	7.56%	0.46%	3.98%	-12.34%	-1.80%	2.50%	6.12%	0.52%	1.36%
BGNMX American Century Ginnie Mae Fund	0.62%	7.43%	0.52%	4.72%	-12.06%	-1.79%	3.73%	6.17%	0.44%	1.22%

Correlation

The correlation between CMPGX and BGNMX 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	0.97
Correlation (5Y) Calculated over the trailing 5-year period	0.97
Correlation (10Y) Calculated over the trailing 10-year period	0.90
Correlation (All Time) Calculated using the full available price history since Sep 24, 1985	0.83

The correlation between CMPGX and BGNMX shifts across timeframes, from 0.83 (all time) to 0.97 (3 years), reflecting how their relationship changes across market environments.

Return for Risk

CMPGX vs. BGNMX — Risk / Return Rank

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

CMPGX

CMPGX Risk / Return Rank: 24
CMPGX Sharpe Ratio Rank: 23
CMPGX Sortino Ratio Rank: 24
CMPGX Omega Ratio Rank: 23
CMPGX Calmar Ratio Rank: 24
CMPGX Martin Ratio Rank: 25

BGNMX

BGNMX Risk / Return Rank: 30
BGNMX Sharpe Ratio Rank: 29
BGNMX Sortino Ratio Rank: 31
BGNMX Omega Ratio Rank: 30
BGNMX Calmar Ratio Rank: 30
BGNMX Martin Ratio Rank: 30

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.

CMPGX vs. BGNMX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Principal Government & High Quality Bond Fund (CMPGX) and American Century Ginnie Mae Fund (BGNMX). 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.

	CMPGX	BGNMX	Difference
Sharpe ratio: Return per unit of total volatility	1.35	1.51	-0.16
Sortino ratio: Return per unit of downside risk	1.98	2.24	-0.26
Omega ratio: Gain probability vs. loss probability	1.24	1.28	-0.03
Calmar ratio: Return relative to maximum drawdown	1.74	2.00	-0.26
Martin ratio: Return relative to average drawdown	5.88	6.72	-0.83
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

CMPGX vs. BGNMX - Sharpe Ratio Comparison

The current CMPGX Sharpe Ratio is 1.35, which is comparable to the BGNMX Sharpe Ratio of 1.51. The chart below compares the historical Sharpe Ratios of CMPGX and BGNMX, 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

	CMPGX	BGNMX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.35	1.51	-0.16
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	-0.09	-0.02	-0.06
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.12	0.18	-0.06
Sharpe Ratio (All Time) Calculated using the full available price history	0.82	0.94	-0.12

Drawdowns

CMPGX vs. BGNMX - Drawdown Comparison

The maximum CMPGX drawdown since its inception was -19.56%, which is greater than BGNMX's maximum drawdown of -18.46%. Use the drawdown chart below to compare losses from any high point for CMPGX and BGNMX.

Drawdown Indicators

	CMPGX	BGNMX	Difference
Max Drawdown Largest peak-to-trough decline	-19.56%	-18.46%	-1.10%
Max Drawdown (1Y) Largest decline over 1 year	-3.39%	-3.07%	-0.32%
Max Drawdown (3Y) Largest decline over 3 years	-8.19%	-7.78%	-0.41%
Max Drawdown (5Y) Largest decline over 5 years	-19.17%	-17.74%	-1.43%
Max Drawdown (10Y) Largest decline over 10 years	-19.56%	-18.46%	-1.10%
Current Drawdown Current decline from peak	-3.59%	-1.72%	-1.87%
Average Drawdown Average peak-to-trough decline	-2.42%	-2.03%	-0.39%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.00%	0.91%	+0.09%

Volatility

CMPGX vs. BGNMX - Volatility Comparison

Principal Government & High Quality Bond Fund (CMPGX) and American Century Ginnie Mae Fund (BGNMX) have volatilities of 1.64% and 1.60%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	CMPGX	BGNMX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.64%	1.60%	+0.04%
Volatility (6M) Calculated over the trailing 6-month period	3.17%	2.99%	+0.18%
Volatility (1Y) Calculated over the trailing 1-year period	4.37%	4.07%	+0.30%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	6.65%	6.45%	+0.20%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	4.97%	4.84%	+0.13%

CMPGX vs. BGNMX - Expense Ratio Comparison

CMPGX has a 0.78% expense ratio, which is higher than BGNMX's 0.55% expense ratio.

Dividends

CMPGX vs. BGNMX - Dividend Comparison

CMPGX's dividend yield for the trailing twelve months is around 3.61%, less than BGNMX's 3.94% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BGNMX American Century Ginnie Mae Fund	3.94%	3.86%	3.70%	3.21%	1.90%	1.64%	2.16%	2.68%	2.65%	2.37%	2.37%	2.37%
CMPGX Principal Government & High Quality Bond Fund	3.61%	3.44%	2.84%	2.19%	1.35%	1.08%	2.00%	2.43%	2.65%	3.30%	3.76%	2.96%

Frequently Asked Questions

Can I hold both CMPGX and BGNMX in my portfolio?

With a correlation of 0.95, CMPGX and BGNMX 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, CMPGX or BGNMX?

CMPGX has higher volatility (1.64%) compared to BGNMX (1.60%). In terms of maximum drawdown, CMPGX dropped -19.56% vs BGNMX's -18.46%.

Which has better risk-adjusted returns?

BGNMX currently has the higher Sharpe Ratio (1.51 vs 1.35), 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.