PNAIX vs. PREIX

Last updated Jun 4, 2026

PNAIX (T. Rowe Price All-Cap Opportunities Fund I Class) and PREIX (T. Rowe Price Equity Index 500 Fund) are both mutual funds - PNAIX is a Large Cap Growth Equities fund tracking the Russell 3000 Index, while PREIX is a Large Cap Blend Equities fund managed by T. Rowe Price. Over the past 10 years, PNAIX returned 15.58%/yr vs 15.42%/yr for PREIX. Their correlation of 0.94 suggests significant overlap in exposure. PNAIX charges 0.66%/yr vs 0.15%/yr for PREIX.

Performance

PNAIX vs. PREIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in T. Rowe Price All-Cap Opportunities Fund I Class (PNAIX) and T. Rowe Price Equity Index 500 Fund (PREIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, PNAIX achieves a 1.18% return, which is significantly lower than PREIX's 11.61% return. Both investments have delivered pretty close results over the past 10 years, with PNAIX having a 15.58% annualized return and PREIX not far behind at 15.42%.

PNAIX

• 1D: 0.18%
• 1M: 3.87%
• YTD: 1.18%
• 6M: 0.75%
• 1Y: 14.87%
• 3Y*: 18.90%
• 5Y*: 10.61%
• 10Y*: 15.58%

PREIX

• 1D: 0.13%
• 1M: 5.78%
• YTD: 11.61%
• 6M: 11.63%
• 1Y: 28.74%
• 3Y*: 22.53%
• 5Y*: 14.08%
• 10Y*: 15.42%

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

PNAIX vs. PREIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
PNAIX T. Rowe Price All-Cap Opportunities Fund I Class	1.18%	16.53%	25.43%	29.18%	-21.25%	20.76%	44.92%	35.66%	1.40%	20.15%
PREIX T. Rowe Price Equity Index 500 Fund	11.61%	17.66%	24.78%	26.07%	-18.27%	28.48%	18.17%	31.47%	-4.59%	21.01%

Correlation

The correlation between PNAIX and PREIX is 0.92, 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	0.92
Correlation (3Y) Calculated over the trailing 3-year period	0.96
Correlation (5Y) Calculated over the trailing 5-year period	0.96
Correlation (10Y) Calculated over the trailing 10-year period	0.94
Correlation (All Time) Calculated using the full available price history since Jan 5, 2016	0.94

The correlation between PNAIX and PREIX has been stable across timeframes, ranging from 0.92 to 0.96 - a consistent structural relationship.

Return for Risk

PNAIX vs. PREIX — Risk / Return Rank

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

PNAIX

PNAIX Risk / Return Rank: 15
PNAIX Sharpe Ratio Rank: 17
PNAIX Sortino Ratio Rank: 17
PNAIX Omega Ratio Rank: 17
PNAIX Calmar Ratio Rank: 12
PNAIX Martin Ratio Rank: 14

PREIX

PREIX Risk / Return Rank: 72
PREIX Sharpe Ratio Rank: 74
PREIX Sortino Ratio Rank: 66
PREIX Omega Ratio Rank: 66
PREIX Calmar Ratio Rank: 73
PREIX Martin Ratio Rank: 82

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.

PNAIX vs. PREIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for T. Rowe Price All-Cap Opportunities Fund I Class (PNAIX) and T. Rowe Price Equity Index 500 Fund (PREIX). 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.

	PNAIX	PREIX	Difference
Sharpe ratio: Return per unit of total volatility	1.18	2.50	-1.32
Sortino ratio: Return per unit of downside risk	1.70	3.40	-1.70
Omega ratio: Gain probability vs. loss probability	1.22	1.45	-0.24
Calmar ratio: Return relative to maximum drawdown	1.11	3.32	-2.20
Martin ratio: Return relative to average drawdown	3.92	15.47	-11.55
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

PNAIX vs. PREIX - Sharpe Ratio Comparison

The current PNAIX Sharpe Ratio is 1.18, which is lower than the PREIX Sharpe Ratio of 2.50. The chart below compares the historical Sharpe Ratios of PNAIX and PREIX, 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

	PNAIX	PREIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.18	2.50	-1.32
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.61	0.83	-0.23
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.82	0.85	-0.04
Sharpe Ratio (All Time) Calculated using the full available price history	0.78	0.61	+0.17

Drawdowns

PNAIX vs. PREIX - Drawdown Comparison

The maximum PNAIX drawdown since its inception was -30.49%, smaller than the maximum PREIX drawdown of -55.32%. Use the drawdown chart below to compare losses from any high point for PNAIX and PREIX.

Drawdown Indicators

	PNAIX	PREIX	Difference
Max Drawdown Largest peak-to-trough decline	-30.49%	-55.32%	+24.83%
Max Drawdown (1Y) Largest decline over 1 year	-14.02%	-8.93%	-5.09%
Max Drawdown (3Y) Largest decline over 3 years	-19.05%	-18.78%	-0.27%
Max Drawdown (5Y) Largest decline over 5 years	-29.29%	-24.60%	-4.69%
Max Drawdown (10Y) Largest decline over 10 years	-30.49%	-33.81%	+3.32%
Current Drawdown Current decline from peak	-0.78%	0.00%	-0.78%
Average Drawdown Average peak-to-trough decline	-5.53%	-8.73%	+3.20%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.97%	1.91%	+2.06%

Volatility

PNAIX vs. PREIX - Volatility Comparison

T. Rowe Price All-Cap Opportunities Fund I Class (PNAIX) has a higher volatility of 3.53% compared to T. Rowe Price Equity Index 500 Fund (PREIX) at 2.83%. This indicates that PNAIX's price experiences larger fluctuations and is considered to be riskier than PREIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	PNAIX	PREIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.53%	2.83%	+0.70%
Volatility (6M) Calculated over the trailing 6-month period	10.56%	8.98%	+1.58%
Volatility (1Y) Calculated over the trailing 1-year period	13.27%	11.87%	+1.40%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.60%	17.00%	+0.60%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	19.16%	18.11%	+1.05%

PNAIX vs. PREIX - Expense Ratio Comparison

PNAIX has a 0.66% expense ratio, which is higher than PREIX's 0.15% expense ratio.

Dividends

PNAIX vs. PREIX - Dividend Comparison

PNAIX's dividend yield for the trailing twelve months is around 8.43%, more than PREIX's 2.10% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PNAIX T. Rowe Price All-Cap Opportunities Fund I Class	8.43%	8.53%	9.37%	5.23%	3.31%	20.62%	15.56%	7.43%	12.75%	0.29%	0.00%	0.00%
PREIX T. Rowe Price Equity Index 500 Fund	2.10%	2.32%	1.17%	1.32%	1.50%	1.56%	1.97%	2.13%	2.60%	1.30%	2.03%	2.02%

Frequently Asked Questions

Can I hold both PNAIX and PREIX in my portfolio?

With a correlation of 0.92, PNAIX and PREIX 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, PNAIX or PREIX?

PNAIX has higher volatility (3.53%) compared to PREIX (2.83%). In terms of maximum drawdown, PNAIX dropped -30.49% vs PREIX's -55.32%.

Which has better risk-adjusted returns?

PREIX currently has the higher Sharpe Ratio (2.50 vs 1.18), 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.