APOIX vs. DFAAX

Last updated Jun 24, 2026

APOIX (American Century Short Duration Inflation Protection Bond Fund Investor Class) and DFAAX (DFA Global Core Plus Real Return Portfolio) are both Inflation-Protected Bonds funds. Over the past 5 years, APOIX returned 2.84%/yr vs 5.08%/yr for DFAAX. A 0.73 correlation means they provide meaningful diversification when combined. APOIX charges 0.57%/yr vs 0.29%/yr for DFAAX.

Performance

APOIX vs. DFAAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX) and DFA Global Core Plus Real Return Portfolio (DFAAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, APOIX achieves a 1.19% return, which is significantly lower than DFAAX's 2.44% return.

APOIX

• 1D: -0.19%
• 1M: -0.35%
• YTD: 1.19%
• 6M: 1.28%
• 1Y: 3.16%
• 3Y*: 4.62%
• 5Y*: 2.84%
• 10Y*: 3.01%

DFAAX

• 1D: -0.30%
• 1M: 0.31%
• YTD: 2.44%
• 6M: 2.44%
• 1Y: 3.89%
• 3Y*: 5.98%
• 5Y*: 5.08%
• 10Y*: —

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

APOIX vs. DFAAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021
APOIX American Century Short Duration Inflation Protection Bond Fund Investor Class	1.19%	5.95%	4.15%	3.82%	-3.89%	3.39%
DFAAX DFA Global Core Plus Real Return Portfolio	2.44%	5.18%	4.41%	9.49%	-13.40%	20.47%

Correlation

The correlation between APOIX and DFAAX is 0.50, 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	0.50
Correlation (3Y) Calculated over the trailing 3-year period	0.67
Correlation (5Y) Calculated over the trailing 5-year period	0.73
Correlation (All Time) Calculated using the full available price history since May 5, 2021	0.73

Over the past year, the correlation between APOIX and DFAAX has dropped to 0.50 - well below their long-term average of 0.73, suggesting their price drivers have been diverging.

Return for Risk

APOIX vs. DFAAX — Risk / Return Rank

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

APOIX

APOIX Risk / Return Rank: 61
APOIX Sharpe Ratio Rank: 43
APOIX Sortino Ratio Rank: 49
APOIX Omega Ratio Rank: 50
APOIX Calmar Ratio Rank: 87
APOIX Martin Ratio Rank: 77

DFAAX

DFAAX Risk / Return Rank: 23
DFAAX Sharpe Ratio Rank: 23
DFAAX Sortino Ratio Rank: 23
DFAAX Omega Ratio Rank: 25
DFAAX Calmar Ratio Rank: 21
DFAAX 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.

APOIX vs. DFAAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX) and DFA Global Core Plus Real Return Portfolio (DFAAX). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	APOIX	DFAAX	Difference
Sharpe ratio: Return per unit of total volatility	1.77	1.27	+0.50
Sortino ratio: Return per unit of downside risk	2.72	1.84	+0.88
Omega ratio: Gain probability vs. loss probability	1.36	1.24	+0.11
Calmar ratio: Return relative to maximum drawdown	3.98	1.55	+2.43
Martin ratio: Return relative to average drawdown	13.40	5.41	+7.99

APOIX vs. DFAAX - Sharpe Ratio Comparison

The current APOIX Sharpe Ratio is 1.77, which is higher than the DFAAX Sharpe Ratio of 1.27. The chart below compares the historical Sharpe Ratios of APOIX and DFAAX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

APOIX vs. DFAAX - Drawdown Comparison

The maximum APOIX drawdown since its inception was -14.54%, smaller than the maximum DFAAX drawdown of -16.64%. Use the drawdown chart below to compare losses from any high point for APOIX and DFAAX.

Drawdown Indicators

	APOIX	DFAAX	Difference
Max Drawdown Largest peak-to-trough decline	-14.54%	-16.64%	+2.10%
Max Drawdown (1Y) Largest decline over 1 year	-0.82%	-2.55%	+1.73%
Max Drawdown (3Y) Largest decline over 3 years	-1.42%	-3.44%	+2.02%
Max Drawdown (5Y) Largest decline over 5 years	-6.58%	-16.64%	+10.06%
Max Drawdown (10Y) Largest decline over 10 years	-6.58%	—	—
Current Drawdown Current decline from peak	-0.82%	-0.61%	-0.21%
Average Drawdown Average peak-to-trough decline	-1.99%	-4.51%	+2.52%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.24%	0.72%	-0.48%

Volatility

APOIX vs. DFAAX - Volatility Comparison

The current volatility for American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX) is 0.67%, while DFA Global Core Plus Real Return Portfolio (DFAAX) has a volatility of 1.00%. This indicates that APOIX experiences smaller price fluctuations and is considered to be less risky than DFAAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	APOIX	DFAAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.67%	1.00%	-0.33%
Volatility (6M) Calculated over the trailing 6-month period	1.35%	2.30%	-0.95%
Volatility (1Y) Calculated over the trailing 1-year period	1.85%	3.12%	-1.27%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.31%	8.37%	-5.06%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.85%	8.28%	-5.43%

APOIX vs. DFAAX - Expense Ratio Comparison

APOIX has a 0.57% expense ratio, which is higher than DFAAX's 0.29% expense ratio.

Dividends

APOIX vs. DFAAX - Dividend Comparison

APOIX's dividend yield for the trailing twelve months is around 4.67%, more than DFAAX's 3.39% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016
APOIX American Century Short Duration Inflation Protection Bond Fund Investor Class	4.67%	3.99%	2.31%	2.78%	5.63%	3.92%	0.81%	1.69%	3.99%	1.52%	0.42%
DFAAX DFA Global Core Plus Real Return Portfolio	3.39%	2.90%	4.09%	3.96%	2.06%	13.05%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both APOIX and DFAAX in my portfolio?

APOIX and DFAAX have a correlation of 0.50, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, APOIX or DFAAX?

DFAAX has higher volatility (1.00%) compared to APOIX (0.67%). In terms of maximum drawdown, APOIX dropped -14.54% vs DFAAX's -16.64%.

Which has better risk-adjusted returns?

APOIX currently has the higher Sharpe Ratio (1.77 vs 1.27), 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.