VADDX vs. VIIIX

Last updated Jun 5, 2026

VADDX (Invesco Equally-Weighted S&P 500 Fund) and VIIIX (Vanguard Institutional Index Fund Institutional Plus Shares) are both S&P 500 funds - VADDX tracks the S&P 500 Equal Weight Index while VIIIX tracks the S&P 500 Index. Both are passively managed. Over the past 10 years, VADDX returned 11.61%/yr vs 15.65%/yr for VIIIX. Their correlation of 0.94 suggests significant overlap in exposure. VADDX charges 0.27%/yr vs 0.02%/yr for VIIIX.

Performance

VADDX vs. VIIIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Invesco Equally-Weighted S&P 500 Fund (VADDX) and Vanguard Institutional Index Fund Institutional Plus Shares (VIIIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, VADDX achieves a 9.59% return, which is significantly lower than VIIIX's 10.88% return. Over the past 10 years, VADDX has underperformed VIIIX with an annualized return of 11.61%, while VIIIX has yielded a comparatively higher 15.65% annualized return.

VADDX

• 1D: -0.42%
• 1M: 2.87%
• YTD: 9.59%
• 6M: 10.02%
• 1Y: 19.62%
• 3Y*: 15.10%
• 5Y*: 8.20%
• 10Y*: 11.61%

VIIIX

• 1D: -0.74%
• 1M: 4.17%
• YTD: 10.88%
• 6M: 10.80%
• 1Y: 28.02%
• 3Y*: 22.87%
• 5Y*: 14.05%
• 10Y*: 15.65%

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

VADDX vs. VIIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
VADDX Invesco Equally-Weighted S&P 500 Fund	9.59%	11.16%	12.68%	13.58%	-11.86%	29.27%	12.56%	28.92%	-7.96%	18.55%
VIIIX Vanguard Institutional Index Fund Institutional Plus Shares	10.88%	17.87%	26.29%	25.79%	-18.14%	28.69%	18.41%	31.48%	-4.41%	21.82%

Correlation

The correlation between VADDX and VIIIX is 0.75, 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	0.75
Correlation (3Y) Calculated over the trailing 3-year period	0.80
Correlation (5Y) Calculated over the trailing 5-year period	0.88
Correlation (10Y) Calculated over the trailing 10-year period	0.89
Correlation (All Time) Calculated using the full available price history since Jul 29, 1997	0.94

The correlation between VADDX and VIIIX shifts across timeframes, from 0.75 (1 year) to 0.94 (all time), reflecting how their relationship changes across market environments.

Return for Risk

VADDX vs. VIIIX — Risk / Return Rank

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

VADDX

VADDX Risk / Return Rank: 37
VADDX Sharpe Ratio Rank: 34
VADDX Sortino Ratio Rank: 34
VADDX Omega Ratio Rank: 32
VADDX Calmar Ratio Rank: 43
VADDX Martin Ratio Rank: 45

VIIIX

VIIIX Risk / Return Rank: 66
VIIIX Sharpe Ratio Rank: 64
VIIIX Sortino Ratio Rank: 59
VIIIX Omega Ratio Rank: 59
VIIIX Calmar Ratio Rank: 67
VIIIX Martin Ratio Rank: 79

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.

VADDX vs. VIIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Invesco Equally-Weighted S&P 500 Fund (VADDX) and Vanguard Institutional Index Fund Institutional Plus Shares (VIIIX). 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.

	VADDX	VIIIX	Difference
Sharpe ratio: Return per unit of total volatility	1.68	2.37	-0.70
Sortino ratio: Return per unit of downside risk	2.44	3.24	-0.80
Omega ratio: Gain probability vs. loss probability	1.29	1.43	-0.14
Calmar ratio: Return relative to maximum drawdown	2.47	3.17	-0.69
Martin ratio: Return relative to average drawdown	9.36	14.79	-5.43
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VADDX vs. VIIIX - Sharpe Ratio Comparison

The current VADDX Sharpe Ratio is 1.68, which is comparable to the VIIIX Sharpe Ratio of 2.37. The chart below compares the historical Sharpe Ratios of VADDX and VIIIX, 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

	VADDX	VIIIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.68	2.37	-0.70
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.51	0.84	-0.33
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.63	0.87	-0.24
Sharpe Ratio (All Time) Calculated using the full available price history	0.47	0.49	-0.02

Drawdowns

VADDX vs. VIIIX - Drawdown Comparison

The maximum VADDX drawdown since its inception was -60.12%, which is greater than VIIIX's maximum drawdown of -55.18%. Use the drawdown chart below to compare losses from any high point for VADDX and VIIIX.

Drawdown Indicators

	VADDX	VIIIX	Difference
Max Drawdown Largest peak-to-trough decline	-60.12%	-55.18%	-4.94%
Max Drawdown (1Y) Largest decline over 1 year	-7.88%	-8.90%	+1.02%
Max Drawdown (3Y) Largest decline over 3 years	-17.86%	-18.75%	+0.89%
Max Drawdown (5Y) Largest decline over 5 years	-21.58%	-24.50%	+2.92%
Max Drawdown (10Y) Largest decline over 10 years	-39.39%	-33.79%	-5.60%
Current Drawdown Current decline from peak	-0.42%	-0.74%	+0.32%
Average Drawdown Average peak-to-trough decline	-7.00%	-10.02%	+3.02%
Ulcer Index Depth and duration of drawdowns from previous peaks	2.07%	1.90%	+0.17%

Volatility

VADDX vs. VIIIX - Volatility Comparison

The current volatility for Invesco Equally-Weighted S&P 500 Fund (VADDX) is 2.60%, while Vanguard Institutional Index Fund Institutional Plus Shares (VIIIX) has a volatility of 2.93%. This indicates that VADDX experiences smaller price fluctuations and is considered to be less risky than VIIIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VADDX	VIIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.60%	2.93%	-0.33%
Volatility (6M) Calculated over the trailing 6-month period	8.39%	8.99%	-0.60%
Volatility (1Y) Calculated over the trailing 1-year period	11.65%	11.88%	-0.23%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.27%	16.89%	-0.62%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.54%	18.06%	+0.48%

VADDX vs. VIIIX - Expense Ratio Comparison

VADDX has a 0.27% expense ratio, which is higher than VIIIX's 0.02% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

VADDX vs. VIIIX - Dividend Comparison

VADDX's dividend yield for the trailing twelve months is around 9.20%, more than VIIIX's 2.43% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
VADDX Invesco Equally-Weighted S&P 500 Fund	9.20%	10.09%	8.88%	4.86%	8.45%	9.92%	6.38%	4.68%	7.13%	2.97%	0.30%	2.98%
VIIIX Vanguard Institutional Index Fund Institutional Plus Shares	2.43%	2.11%	3.66%	2.66%	3.39%	4.79%	3.07%	2.86%	2.45%	1.84%	2.38%	2.47%

Frequently Asked Questions

Can I hold both VADDX and VIIIX in my portfolio?

VADDX and VIIIX have a correlation of 0.75, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, VADDX or VIIIX?

VIIIX has higher volatility (2.93%) compared to VADDX (2.60%). In terms of maximum drawdown, VADDX dropped -60.12% vs VIIIX's -55.18%.

Which has better risk-adjusted returns?

VIIIX currently has the higher Sharpe Ratio (2.37 vs 1.68), 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.