PRIPX vs. APOIX

Last updated Jun 4, 2026

PRIPX (T. Rowe Price Inflation Protected Bond Fund) and APOIX (American Century Short Duration Inflation Protection Bond Fund Investor Class) are both Inflation-Protected Bonds funds. Over the past 10 years, PRIPX returned 2.26%/yr vs 3.13%/yr for APOIX. Their correlation of 0.81 suggests significant overlap in exposure. PRIPX charges 0.38%/yr vs 0.57%/yr for APOIX.

Performance

PRIPX vs. APOIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in T. Rowe Price Inflation Protected Bond Fund (PRIPX) 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

In the year-to-date period, PRIPX achieves a 1.50% return, which is significantly lower than APOIX's 2.02% return. Over the past 10 years, PRIPX has underperformed APOIX with an annualized return of 2.26%, while APOIX has yielded a comparatively higher 3.13% annualized return.

PRIPX

• 1D: 0.00%
• 1M: 0.03%
• YTD: 1.50%
• 6M: 1.27%
• 1Y: 5.49%
• 3Y*: 2.88%
• 5Y*: 0.11%
• 10Y*: 2.26%

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)

PRIPX vs. APOIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
PRIPX T. Rowe Price Inflation Protected Bond Fund	1.50%	7.34%	-1.27%	2.57%	-12.76%	5.45%	11.07%	10.31%	-1.33%	2.75%
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 PRIPX and APOIX is 0.71, 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	0.71
Correlation (3Y) Calculated over the trailing 3-year period	0.79
Correlation (5Y) Calculated over the trailing 5-year period	0.80
Correlation (10Y) Calculated over the trailing 10-year period	0.76
Correlation (All Time) Calculated using the full available price history since Jun 1, 2005	0.81

The correlation between PRIPX and APOIX shifts across timeframes, from 0.71 (1 year) to 0.81 (all time), reflecting how their relationship changes across market environments.

Return for Risk

PRIPX vs. APOIX — Risk / Return Rank

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

PRIPX

PRIPX Risk / Return Rank: 14
PRIPX Sharpe Ratio Rank: 11
PRIPX Sortino Ratio Rank: 11
PRIPX Omega Ratio Rank: 25
PRIPX Calmar Ratio Rank: 14
PRIPX Martin Ratio Rank: 8

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.

PRIPX vs. APOIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for T. Rowe Price Inflation Protected Bond Fund (PRIPX) 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.

	PRIPX	APOIX	Difference
Sharpe ratio Return per unit of total volatility	0.89	2.45	-1.56
Sortino ratio Return per unit of downside risk	1.34	4.00	-2.66
Omega ratio Gain probability vs. loss probability	1.26	1.51	-0.25
Calmar ratio Return relative to maximum drawdown	1.29	5.81	-4.52
Martin ratio Return relative to average drawdown	2.31	19.09	-16.78
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

PRIPX vs. APOIX - Sharpe Ratio Comparison

The current PRIPX Sharpe Ratio is 0.89, which is lower than the APOIX Sharpe Ratio of 2.45. The chart below compares the historical Sharpe Ratios of PRIPX 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

	PRIPX	APOIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.89	2.45	-1.56
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.02	0.90	-0.88
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.38	1.10	-0.73
Sharpe Ratio (All Time) Calculated using the full available price history	0.57	0.72	-0.14

Drawdowns

PRIPX vs. APOIX - Drawdown Comparison

The maximum PRIPX 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 PRIPX and APOIX.

Drawdown Indicators

	PRIPX	APOIX	Difference
Max Drawdown Largest peak-to-trough decline	-16.15%	-14.54%	-1.61%
Max Drawdown (1Y) Largest decline over 1 year	-4.21%	-0.76%	-3.45%
Max Drawdown (3Y) Largest decline over 3 years	-6.90%	-1.42%	-5.48%
Max Drawdown (5Y) Largest decline over 5 years	-16.15%	-6.58%	-9.57%
Max Drawdown (10Y) Largest decline over 10 years	-16.15%	-6.58%	-9.57%
Current Drawdown Current decline from peak	-4.63%	-0.00%	-4.63%
Average Drawdown Average peak-to-trough decline	-4.05%	-1.99%	-2.06%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.34%	0.23%	+2.11%

Volatility

PRIPX vs. APOIX - Volatility Comparison

T. Rowe Price Inflation Protected Bond Fund (PRIPX) has a higher volatility of 0.94% compared to American Century Short Duration Inflation Protection Bond Fund Investor Class (APOIX) at 0.51%. This indicates that PRIPX'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

	PRIPX	APOIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.94%	0.51%	+0.43%
Volatility (6M) Calculated over the trailing 6-month period	2.29%	1.25%	+1.04%
Volatility (1Y) Calculated over the trailing 1-year period	6.07%	1.81%	+4.26%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	7.02%	3.31%	+3.71%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	6.03%	2.85%	+3.18%

PRIPX vs. APOIX - Expense Ratio Comparison

PRIPX has a 0.38% expense ratio, which is lower than APOIX's 0.57% expense ratio.

Dividends

PRIPX vs. APOIX - Dividend Comparison

PRIPX's dividend yield for the trailing twelve months is around 5.41%, more than APOIX's 3.91% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
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%	0.00%
PRIPX T. Rowe Price Inflation Protected Bond Fund	5.41%	5.63%	1.49%	5.02%	7.37%	5.30%	1.97%	3.81%	3.02%	1.87%	1.32%	1.76%

Frequently Asked Questions

Can I hold both PRIPX and APOIX in my portfolio?

PRIPX and APOIX have a correlation of 0.71, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, PRIPX or APOIX?

PRIPX has higher volatility (0.94%) compared to APOIX (0.51%). In terms of maximum drawdown, PRIPX dropped -16.15% vs APOIX's -14.54%.

Which has better risk-adjusted returns?

APOIX currently has the higher Sharpe Ratio (2.45 vs 0.89), 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.