FSSNX vs. IDMO

Last updated Jun 13, 2026

FSSNX (Fidelity Small Cap Index Fund) and IDMO (Invesco S&P International Developed Momentum ETF) are both funds - FSSNX is a Small Cap Blend Equities fund tracking the Russell 2000 Index, while IDMO is a Momentum fund tracking the S&P Momentum Developed ex U.S. & South Korea LargeMidCap Index. Both are passively managed. Over the past 10 years, FSSNX returned 11.30%/yr vs 12.64%/yr for IDMO. At a 0.48 correlation, their price movements are largely independent. FSSNX charges 0.03%/yr vs 0.25%/yr for IDMO.

Performance

FSSNX vs. IDMO - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Small Cap Index Fund (FSSNX) and Invesco S&P International Developed Momentum ETF (IDMO). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FSSNX achieves a 18.33% return, which is significantly higher than IDMO's 8.17% return. Over the past 10 years, FSSNX has underperformed IDMO with an annualized return of 11.30%, while IDMO has yielded a comparatively higher 12.64% annualized return.

FSSNX

• 1D: 3.04%
• 1M: 2.84%
• YTD: 18.33%
• 6M: 15.24%
• 1Y: 38.39%
• 3Y*: 17.71%
• 5Y*: 6.13%
• 10Y*: 11.30%

IDMO

• 1D: 1.36%
• 1M: -1.92%
• YTD: 8.17%
• 6M: 10.09%
• 1Y: 23.12%
• 3Y*: 25.21%
• 5Y*: 15.50%
• 10Y*: 12.64%

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

FSSNX vs. IDMO - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FSSNX Fidelity Small Cap Index Fund	18.33%	12.94%	11.71%	17.11%	-20.28%	14.70%	19.99%	25.70%	-11.24%	14.54%
IDMO Invesco S&P International Developed Momentum ETF	8.17%	42.17%	12.79%	20.16%	-12.03%	14.31%	22.01%	26.09%	-16.66%	29.21%

Correlation

The correlation between FSSNX and IDMO is 0.69, 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	0.69
Correlation (3Y) Calculated over the trailing 3-year period	0.66
Correlation (5Y) Calculated over the trailing 5-year period	0.68
Correlation (10Y) Calculated over the trailing 10-year period	0.55
Correlation (All Time) Calculated using the full available price history since Feb 24, 2012	0.48

Over the past year, FSSNX and IDMO have become more correlated (0.69) than their long-term average of 0.48, meaning their price movements have been converging.

Return for Risk

FSSNX vs. IDMO — Risk / Return Rank

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

FSSNX

FSSNX Risk / Return Rank: 73
FSSNX Sharpe Ratio Rank: 70
FSSNX Sortino Ratio Rank: 68
FSSNX Omega Ratio Rank: 57
FSSNX Calmar Ratio Rank: 86
FSSNX Martin Ratio Rank: 82

IDMO

IDMO Risk / Return Rank: 44
IDMO Sharpe Ratio Rank: 42
IDMO Sortino Ratio Rank: 43
IDMO Omega Ratio Rank: 42
IDMO Calmar Ratio Rank: 43
IDMO Martin Ratio Rank: 51

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.

FSSNX vs. IDMO - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Small Cap Index Fund (FSSNX) and Invesco S&P International Developed Momentum ETF (IDMO). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	FSSNX	IDMO	Difference
Sharpe ratio: Return per unit of total volatility	1.93	1.30	+0.63
Sortino ratio: Return per unit of downside risk	2.68	1.93	+0.75
Omega ratio: Gain probability vs. loss probability	1.32	1.24	+0.07
Calmar ratio: Return relative to maximum drawdown	3.46	1.89	+1.57
Martin ratio: Return relative to average drawdown	12.23	7.64	+4.59

FSSNX vs. IDMO - Sharpe Ratio Comparison

The current FSSNX Sharpe Ratio is 1.93, which is higher than the IDMO Sharpe Ratio of 1.30. The chart below compares the historical Sharpe Ratios of FSSNX and IDMO, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

FSSNX vs. IDMO - Drawdown Comparison

The maximum FSSNX drawdown since its inception was -41.72%, which is greater than IDMO's maximum drawdown of -39.38%. Use the drawdown chart below to compare losses from any high point for FSSNX and IDMO.

Drawdown Indicators

	FSSNX	IDMO	Difference
Max Drawdown Largest peak-to-trough decline	-41.72%	-39.38%	-2.34%
Max Drawdown (1Y) Largest decline over 1 year	-11.00%	-12.31%	+1.31%
Max Drawdown (3Y) Largest decline over 3 years	-27.45%	-12.65%	-14.80%
Max Drawdown (5Y) Largest decline over 5 years	-31.87%	-27.07%	-4.80%
Max Drawdown (10Y) Largest decline over 10 years	-41.72%	-31.34%	-10.38%
Current Drawdown Current decline from peak	-0.46%	-1.92%	+1.46%
Average Drawdown Average peak-to-trough decline	-8.28%	-9.74%	+1.46%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.11%	3.04%	+0.07%

Volatility

FSSNX vs. IDMO - Volatility Comparison

The current volatility for Fidelity Small Cap Index Fund (FSSNX) is 7.09%, while Invesco S&P International Developed Momentum ETF (IDMO) has a volatility of 7.92%. This indicates that FSSNX experiences smaller price fluctuations and is considered to be less risky than IDMO based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FSSNX	IDMO	Difference
Volatility (1M) Calculated over the trailing 1-month period	7.09%	7.92%	-0.83%
Volatility (6M) Calculated over the trailing 6-month period	14.37%	16.02%	-1.65%
Volatility (1Y) Calculated over the trailing 1-year period	19.71%	17.92%	+1.79%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	22.68%	18.03%	+4.65%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	23.49%	18.18%	+5.31%

FSSNX vs. IDMO - Expense Ratio Comparison

FSSNX has a 0.03% expense ratio, which is lower than IDMO's 0.25% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

FSSNX vs. IDMO - Dividend Comparison

FSSNX's dividend yield for the trailing twelve months is around 0.92%, less than IDMO's 3.52% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FSSNX Fidelity Small Cap Index Fund	0.92%	1.08%	1.04%	1.43%	1.26%	3.92%	0.94%	2.96%	4.94%	3.37%	2.27%	2.66%
IDMO Invesco S&P International Developed Momentum ETF	3.52%	3.71%	2.24%	2.89%	3.66%	1.81%	1.63%	2.78%	3.27%	3.08%	2.18%	2.52%

Frequently Asked Questions

Can I hold both FSSNX and IDMO in my portfolio?

FSSNX and IDMO have a correlation of 0.69, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, FSSNX or IDMO?

IDMO has higher volatility (7.92%) compared to FSSNX (7.09%). In terms of maximum drawdown, FSSNX dropped -41.72% vs IDMO's -39.38%.

Which has better risk-adjusted returns?

FSSNX currently has the higher Sharpe Ratio (1.93 vs 1.30), 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.