OPOCX vs. FXAIX

Last updated Jun 4, 2026

OPOCX (Invesco Discovery Fund) and FXAIX (Fidelity 500 Index Fund) are both mutual funds - OPOCX is a Small Cap Growth Equities fund managed by Invesco, while FXAIX is a S&P 500 fund tracking the S&P 500 Index. Over the past 10 years, OPOCX returned 16.53%/yr vs 15.66%/yr for FXAIX. Their correlation of 0.82 suggests significant overlap in exposure. OPOCX charges 1.01%/yr vs 0.02%/yr for FXAIX.

Performance

OPOCX vs. FXAIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Invesco Discovery Fund (OPOCX) and Fidelity 500 Index Fund (FXAIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, OPOCX achieves a 30.98% return, which is significantly higher than FXAIX's 11.71% return. Over the past 10 years, OPOCX has outperformed FXAIX with an annualized return of 16.53%, while FXAIX has yielded a comparatively lower 15.66% annualized return.

OPOCX

• 1D: 2.40%
• 1M: 5.92%
• YTD: 30.98%
• 6M: 31.47%
• 1Y: 56.26%
• 3Y*: 26.88%
• 5Y*: 10.85%
• 10Y*: 16.53%

FXAIX

• 1D: 0.13%
• 1M: 5.80%
• YTD: 11.71%
• 6M: 11.74%
• 1Y: 28.99%
• 3Y*: 22.75%
• 5Y*: 14.28%
• 10Y*: 15.66%

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

OPOCX vs. FXAIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
OPOCX Invesco Discovery Fund	30.98%	16.77%	22.61%	17.02%	-31.26%	14.78%	50.33%	36.81%	-4.15%	29.04%
FXAIX Fidelity 500 Index Fund	11.71%	17.84%	25.01%	26.29%	-18.14%	28.71%	18.42%	31.48%	-4.43%	21.82%

Correlation

The correlation between OPOCX and FXAIX is 0.77, 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	0.77
Correlation (3Y) Calculated over the trailing 3-year period	0.80
Correlation (5Y) Calculated over the trailing 5-year period	0.83
Correlation (10Y) Calculated over the trailing 10-year period	0.81
Correlation (All Time) Calculated using the full available price history since May 5, 2011	0.82

The correlation between OPOCX and FXAIX has been stable across timeframes, ranging from 0.77 to 0.83 - a consistent structural relationship.

Return for Risk

OPOCX vs. FXAIX — Risk / Return Rank

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

OPOCX

OPOCX Risk / Return Rank: 71
OPOCX Sharpe Ratio Rank: 67
OPOCX Sortino Ratio Rank: 53
OPOCX Omega Ratio Rank: 51
OPOCX Calmar Ratio Rank: 93
OPOCX Martin Ratio Rank: 93

FXAIX

FXAIX Risk / Return Rank: 73
FXAIX Sharpe Ratio Rank: 76
FXAIX Sortino Ratio Rank: 67
FXAIX Omega Ratio Rank: 67
FXAIX Calmar Ratio Rank: 74
FXAIX Martin Ratio Rank: 83

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.

OPOCX vs. FXAIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Invesco Discovery Fund (OPOCX) and Fidelity 500 Index Fund (FXAIX). 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.

	OPOCX	FXAIX	Difference
Sharpe ratio: Return per unit of total volatility	2.39	2.52	-0.13
Sortino ratio: Return per unit of downside risk	3.07	3.42	-0.35
Omega ratio: Gain probability vs. loss probability	1.39	1.46	-0.06
Calmar ratio: Return relative to maximum drawdown	5.12	3.36	+1.76
Martin ratio: Return relative to average drawdown	20.36	15.70	+4.67
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

OPOCX vs. FXAIX - Sharpe Ratio Comparison

The current OPOCX Sharpe Ratio is 2.39, which is comparable to the FXAIX Sharpe Ratio of 2.52. The chart below compares the historical Sharpe Ratios of OPOCX and FXAIX, 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

	OPOCX	FXAIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.39	2.52	-0.13
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.43	0.85	-0.42
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.67	0.87	-0.20
Sharpe Ratio (All Time) Calculated using the full available price history	0.51	0.82	-0.31

Drawdowns

OPOCX vs. FXAIX - Drawdown Comparison

The maximum OPOCX drawdown since its inception was -64.17%, which is greater than FXAIX's maximum drawdown of -33.79%. Use the drawdown chart below to compare losses from any high point for OPOCX and FXAIX.

Drawdown Indicators

	OPOCX	FXAIX	Difference
Max Drawdown Largest peak-to-trough decline	-64.17%	-33.79%	-30.38%
Max Drawdown (1Y) Largest decline over 1 year	-11.38%	-8.89%	-2.49%
Max Drawdown (3Y) Largest decline over 3 years	-28.60%	-18.76%	-9.84%
Max Drawdown (5Y) Largest decline over 5 years	-43.27%	-24.50%	-18.77%
Max Drawdown (10Y) Largest decline over 10 years	-43.27%	-33.79%	-9.48%
Current Drawdown Current decline from peak	-0.18%	0.00%	-0.18%
Average Drawdown Average peak-to-trough decline	-18.87%	-3.79%	-15.08%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.85%	1.90%	+0.95%

Volatility

OPOCX vs. FXAIX - Volatility Comparison

Invesco Discovery Fund (OPOCX) has a higher volatility of 7.85% compared to Fidelity 500 Index Fund (FXAIX) at 2.83%. This indicates that OPOCX's price experiences larger fluctuations and is considered to be riskier than FXAIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	OPOCX	FXAIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	7.85%	2.83%	+5.02%
Volatility (6M) Calculated over the trailing 6-month period	20.07%	8.97%	+11.10%
Volatility (1Y) Calculated over the trailing 1-year period	24.38%	11.86%	+12.52%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	25.39%	16.91%	+8.48%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	24.85%	18.07%	+6.78%

OPOCX vs. FXAIX - Expense Ratio Comparison

OPOCX has a 1.01% expense ratio, which is higher than FXAIX's 0.02% expense ratio.

Dividends

OPOCX vs. FXAIX - Dividend Comparison

OPOCX's dividend yield for the trailing twelve months is around 10.24%, more than FXAIX's 1.03% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FXAIX Fidelity 500 Index Fund	1.03%	1.11%	1.25%	1.45%	1.69%	1.22%	1.60%	2.06%	2.72%	1.97%	2.52%	2.83%
OPOCX Invesco Discovery Fund	10.24%	13.41%	6.86%	0.00%	0.00%	20.51%	11.22%	6.42%	18.85%	12.46%	4.33%	6.84%

Frequently Asked Questions

Can I hold both OPOCX and FXAIX in my portfolio?

OPOCX and FXAIX have a correlation of 0.77, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, OPOCX or FXAIX?

OPOCX has higher volatility (7.85%) compared to FXAIX (2.83%). In terms of maximum drawdown, OPOCX dropped -64.17% vs FXAIX's -33.79%.

Which has better risk-adjusted returns?

FXAIX currently has the higher Sharpe Ratio (2.52 vs 2.39), 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.