SPIDX vs. SPFIX

Last updated Jun 4, 2026

SPIDX (Invesco S&P 500 Index Fund) and SPFIX (Shelton Capital Management S&P 500 Index Fund) are both S&P 500 funds tracking the S&P 500 Index, from Invesco and BlackRock respectively. Both are passively managed. Over the past 10 years, SPIDX returned 15.33%/yr vs 17.69%/yr for SPFIX. With a 1.00 correlation, they move nearly in lockstep. SPIDX charges 0.29%/yr vs 0.43%/yr for SPFIX.

Performance

SPIDX vs. SPFIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Invesco S&P 500 Index Fund (SPIDX) and Shelton Capital Management S&P 500 Index Fund (SPFIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both stocks are quite close, with SPIDX having a 11.58% return and SPFIX slightly lower at 11.42%. Over the past 10 years, SPIDX has underperformed SPFIX with an annualized return of 15.33%, while SPFIX has yielded a comparatively higher 17.69% annualized return.

SPIDX

• 1D: 0.14%
• 1M: 5.78%
• YTD: 11.58%
• 6M: 11.63%
• 1Y: 28.68%
• 3Y*: 22.41%
• 5Y*: 13.96%
• 10Y*: 15.33%

SPFIX

• 1D: 0.14%
• 1M: 5.71%
• YTD: 11.42%
• 6M: 11.42%
• 1Y: 28.45%
• 3Y*: 27.82%
• 5Y*: 16.92%
• 10Y*: 17.69%

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

SPIDX vs. SPFIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SPIDX Invesco S&P 500 Index Fund	11.58%	17.54%	24.65%	25.95%	-18.36%	28.30%	18.13%	31.11%	-4.75%	21.45%
SPFIX Shelton Capital Management S&P 500 Index Fund	11.42%	17.23%	42.83%	25.48%	-18.22%	27.99%	17.41%	41.64%	-4.68%	21.55%

Correlation

The correlation between SPIDX and SPFIX is 1.00 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	1.00
Correlation (3Y) Calculated over the trailing 3-year period	1.00
Correlation (5Y) Calculated over the trailing 5-year period	1.00
Correlation (10Y) Calculated over the trailing 10-year period	1.00
Correlation (All Time) Calculated using the full available price history since Jan 5, 1998	1.00

The correlation between SPIDX and SPFIX has been stable across timeframes, ranging from 0.99 to 1.00 - a consistent structural relationship.

Return for Risk

SPIDX vs. SPFIX — Risk / Return Rank

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

SPIDX

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

SPFIX

SPFIX Risk / Return Rank: 72
SPFIX Sharpe Ratio Rank: 73
SPFIX Sortino Ratio Rank: 66
SPFIX Omega Ratio Rank: 65
SPFIX Calmar Ratio Rank: 72
SPFIX 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.

SPIDX vs. SPFIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Invesco S&P 500 Index Fund (SPIDX) and Shelton Capital Management S&P 500 Index Fund (SPFIX). 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.

	SPIDX	SPFIX	Difference
Sharpe ratio Return per unit of total volatility	2.50	2.48	+0.01
Sortino ratio Return per unit of downside risk	3.40	3.38	+0.01
Omega ratio Gain probability vs. loss probability	1.45	1.45	0.00
Calmar ratio Return relative to maximum drawdown	3.32	3.29	+0.03
Martin ratio Return relative to average drawdown	15.49	15.35	+0.14
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

SPIDX vs. SPFIX - Sharpe Ratio Comparison

The current SPIDX Sharpe Ratio is 2.50, which is comparable to the SPFIX Sharpe Ratio of 2.48. The chart below compares the historical Sharpe Ratios of SPIDX and SPFIX, 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

	SPIDX	SPFIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.50	2.48	+0.01
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.83	0.93	-0.10
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.85	0.94	-0.09
Sharpe Ratio (All Time) Calculated using the full available price history	0.47	0.59	-0.12

Drawdowns

SPIDX vs. SPFIX - Drawdown Comparison

The maximum SPIDX drawdown since its inception was -55.30%, roughly equal to the maximum SPFIX drawdown of -54.81%. Use the drawdown chart below to compare losses from any high point for SPIDX and SPFIX.

Drawdown Indicators

	SPIDX	SPFIX	Difference
Max Drawdown Largest peak-to-trough decline	-55.30%	-54.81%	-0.49%
Max Drawdown (1Y) Largest decline over 1 year	-8.93%	-8.90%	-0.03%
Max Drawdown (3Y) Largest decline over 3 years	-18.81%	-18.94%	+0.13%
Max Drawdown (5Y) Largest decline over 5 years	-24.66%	-24.69%	+0.03%
Max Drawdown (10Y) Largest decline over 10 years	-33.84%	-33.83%	-0.01%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-10.51%	-8.95%	-1.56%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.91%	1.91%	0.00%

Volatility

SPIDX vs. SPFIX - Volatility Comparison

Invesco S&P 500 Index Fund (SPIDX) and Shelton Capital Management S&P 500 Index Fund (SPFIX) have volatilities of 2.82% and 2.82%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SPIDX	SPFIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.82%	2.82%	0.00%
Volatility (6M) Calculated over the trailing 6-month period	8.99%	8.93%	+0.06%
Volatility (1Y) Calculated over the trailing 1-year period	11.89%	11.81%	+0.08%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.91%	18.23%	-1.32%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.09%	18.88%	-0.79%

SPIDX vs. SPFIX - Expense Ratio Comparison

SPIDX has a 0.29% expense ratio, which is lower than SPFIX's 0.43% expense ratio.

Dividends

SPIDX vs. SPFIX - Dividend Comparison

SPIDX's dividend yield for the trailing twelve months is around 0.96%, less than SPFIX's 3.26% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
SPFIX Shelton Capital Management S&P 500 Index Fund	3.26%	3.45%	27.20%	8.08%	5.07%	5.43%	8.06%	16.60%	2.49%	3.01%	2.92%	4.35%
SPIDX Invesco S&P 500 Index Fund	0.96%	1.07%	1.28%	1.23%	1.14%	2.09%	1.45%	2.11%	2.82%	1.49%	1.49%	1.74%

Frequently Asked Questions

Can I hold both SPIDX and SPFIX in my portfolio?

With a correlation of 1.00, SPIDX and SPFIX 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, SPIDX or SPFIX?

SPFIX has higher volatility (2.82%) compared to SPIDX (2.82%). In terms of maximum drawdown, SPIDX dropped -55.30% vs SPFIX's -54.81%.

Which has better risk-adjusted returns?

SPIDX currently has the higher Sharpe Ratio (2.50 vs 2.48), 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.