RRPAX vs. APOIX

Last updated Jun 4, 2026

RRPAX (SEI Institutional Investments Trust Real Return Fund) and APOIX (American Century Short Duration Inflation Protection Bond Fund Investor Class) are both Inflation-Protected Bonds funds. Over the past 10 years, RRPAX returned 2.98%/yr vs 3.13%/yr for APOIX. Their correlation of 0.81 suggests significant overlap in exposure. RRPAX charges 0.02%/yr vs 0.57%/yr for APOIX.

Performance

RRPAX vs. APOIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in SEI Institutional Investments Trust Real Return Fund (RRPAX) and American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both investments are quite close, with RRPAX having a 1.97% return and APOIX slightly higher at 2.02%. Over the past 10 years, RRPAX has underperformed APOIX with an annualized return of 2.98%, while APOIX has yielded a comparatively higher 3.13% annualized return.

RRPAX

• 1D: 0.00%
• 1M: 0.00%
• YTD: 1.97%
• 6M: 1.88%
• 1Y: 4.69%
• 3Y*: 4.96%
• 5Y*: 2.95%
• 10Y*: 2.98%

APOIX

• 1D: 0.00%
• 1M: -0.00%
• YTD: 2.02%
• 6M: 1.90%
• 1Y: 4.51%
• 3Y*: 4.85%
• 5Y*: 2.96%
• 10Y*: 3.13%

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

RRPAX vs. APOIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
RRPAX SEI Institutional Investments Trust Real Return Fund	1.97%	6.53%	4.54%	3.49%	-4.06%	5.41%	5.64%	5.01%	0.31%	0.73%
APOIX American Century Short Duration Inflation Protection Bond Fund Investor Class	2.02%	5.95%	4.15%	3.82%	-3.89%	6.30%	5.06%	4.77%	1.81%	0.73%

Correlation

The correlation between RRPAX and APOIX is 0.81, 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	0.81
Correlation (3Y) Calculated over the trailing 3-year period	0.87
Correlation (5Y) Calculated over the trailing 5-year period	0.90
Correlation (10Y) Calculated over the trailing 10-year period	0.84
Correlation (All Time) Calculated using the full available price history since Jan 4, 2007	0.81

The correlation between RRPAX and APOIX has been stable across timeframes, ranging from 0.81 to 0.90 - a consistent structural relationship.

Return for Risk

RRPAX vs. APOIX — Risk / Return Rank

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

RRPAX

RRPAX Risk / Return Rank: 86
RRPAX Sharpe Ratio Rank: 74
RRPAX Sortino Ratio Rank: 87
RRPAX Omega Ratio Rank: 82
RRPAX Calmar Ratio Rank: 94
RRPAX Martin Ratio Rank: 93

APOIX

APOIX Risk / Return Rank: 84
APOIX Sharpe Ratio Rank: 71
APOIX Sortino Ratio Rank: 84
APOIX Omega Ratio Rank: 78
APOIX Calmar Ratio Rank: 95
APOIX Martin Ratio Rank: 91

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.

RRPAX vs. APOIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for SEI Institutional Investments Trust Real Return Fund (RRPAX) and American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX). 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.

	RRPAX	APOIX	Difference
Sharpe ratio: Return per unit of total volatility	2.50	2.45	+0.05
Sortino ratio: Return per unit of downside risk	4.13	4.00	+0.13
Omega ratio: Gain probability vs. loss probability	1.55	1.51	+0.04
Calmar ratio: Return relative to maximum drawdown	5.40	5.81	-0.40
Martin ratio: Return relative to average drawdown	20.03	19.09	+0.93
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

RRPAX vs. APOIX - Sharpe Ratio Comparison

The current RRPAX Sharpe Ratio is 2.50, which is comparable to the APOIX Sharpe Ratio of 2.45. The chart below compares the historical Sharpe Ratios of RRPAX and APOIX, 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

	RRPAX	APOIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.50	2.45	+0.05
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.92	0.90	+0.02
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	1.11	1.10	+0.01
Sharpe Ratio (All Time) Calculated using the full available price history	0.52	0.72	-0.20

Drawdowns

RRPAX vs. APOIX - Drawdown Comparison

The maximum RRPAX drawdown since its inception was -16.15%, which is greater than APOIX's maximum drawdown of -14.54%. Use the drawdown chart below to compare losses from any high point for RRPAX and APOIX.

Drawdown Indicators

	RRPAX	APOIX	Difference
Max Drawdown Largest peak-to-trough decline	-16.15%	-14.54%	-1.61%
Max Drawdown (1Y) Largest decline over 1 year	-0.85%	-0.76%	-0.09%
Max Drawdown (3Y) Largest decline over 3 years	-1.89%	-1.42%	-0.47%
Max Drawdown (5Y) Largest decline over 5 years	-6.48%	-6.58%	+0.10%
Max Drawdown (10Y) Largest decline over 10 years	-6.48%	-6.58%	+0.10%
Current Drawdown Current decline from peak	-0.11%	-0.00%	-0.11%
Average Drawdown Average peak-to-trough decline	-2.95%	-1.99%	-0.96%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.23%	0.23%	0.00%

Volatility

RRPAX vs. APOIX - Volatility Comparison

SEI Institutional Investments Trust Real Return Fund (RRPAX) has a higher volatility of 0.58% compared to American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX) at 0.51%. This indicates that RRPAX's price experiences larger fluctuations and is considered to be riskier than APOIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	RRPAX	APOIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.58%	0.51%	+0.07%
Volatility (6M) Calculated over the trailing 6-month period	1.32%	1.25%	+0.07%
Volatility (1Y) Calculated over the trailing 1-year period	1.84%	1.81%	+0.03%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.24%	3.31%	-0.07%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.70%	2.85%	-0.15%

RRPAX vs. APOIX - Expense Ratio Comparison

RRPAX has a 0.02% expense ratio, which is lower than APOIX's 0.57% expense ratio.

Dividends

RRPAX vs. APOIX - Dividend Comparison

RRPAX's dividend yield for the trailing twelve months is around 3.92%, which matches APOIX's 3.91% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016
APOIX American Century Short Duration Inflation Protection Bond Fund Investor Class	3.91%	3.99%	2.31%	2.78%	5.63%	3.92%	0.81%	1.69%	3.99%	1.52%	0.42%
RRPAX SEI Institutional Investments Trust Real Return Fund	3.92%	4.64%	3.57%	2.43%	7.18%	5.33%	1.38%	2.14%	2.35%	1.89%	1.23%

Frequently Asked Questions

Can I hold both RRPAX and APOIX in my portfolio?

RRPAX and APOIX have a correlation of 0.81, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, RRPAX or APOIX?

RRPAX has higher volatility (0.58%) compared to APOIX (0.51%). In terms of maximum drawdown, RRPAX dropped -16.15% vs APOIX's -14.54%.

Which has better risk-adjusted returns?

RRPAX currently has the higher Sharpe Ratio (2.50 vs 2.45), 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.