AIOIX vs. FSISX

Last updated Jun 4, 2026

AIOIX (American Century International Opportunities Fund) and FSISX (Fidelity SAI International Small Cap Index Fund) are both Foreign Small & Mid Cap Equities funds. Over the past 5 years, AIOIX returned 2.92%/yr vs 5.61%/yr for FSISX. Their correlation of 0.89 suggests significant overlap in exposure. AIOIX charges 1.48%/yr vs 0.10%/yr for FSISX.

Performance

AIOIX vs. FSISX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in American Century International Opportunities Fund (AIOIX) and Fidelity SAI International Small Cap Index Fund (FSISX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, AIOIX achieves a 15.88% return, which is significantly higher than FSISX's 10.30% return.

AIOIX

• 1D: -0.15%
• 1M: 2.46%
• YTD: 15.88%
• 6M: 18.09%
• 1Y: 32.80%
• 3Y*: 15.62%
• 5Y*: 2.92%
• 10Y*: 8.30%

FSISX

• 1D: -0.09%
• 1M: 2.87%
• YTD: 10.30%
• 6M: 13.47%
• 1Y: 25.30%
• 3Y*: 16.81%
• 5Y*: 5.61%
• 10Y*: —

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

AIOIX vs. FSISX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021
AIOIX American Century International Opportunities Fund	15.88%	29.62%	1.31%	8.63%	-30.19%	0.65%
FSISX Fidelity SAI International Small Cap Index Fund	10.30%	32.61%	1.74%	13.23%	-21.18%	-0.40%

Correlation

The correlation between AIOIX and FSISX is 0.85, 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	0.85
Correlation (3Y) Calculated over the trailing 3-year period	0.85
Correlation (5Y) Calculated over the trailing 5-year period	0.89
Correlation (All Time) Calculated using the full available price history since May 28, 2021	0.89

The correlation between AIOIX and FSISX has been stable across timeframes, ranging from 0.85 to 0.89 - a consistent structural relationship.

Return for Risk

AIOIX vs. FSISX — Risk / Return Rank

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

AIOIX

AIOIX Risk / Return Rank: 37
AIOIX Sharpe Ratio Rank: 35
AIOIX Sortino Ratio Rank: 32
AIOIX Omega Ratio Rank: 34
AIOIX Calmar Ratio Rank: 37
AIOIX Martin Ratio Rank: 44

FSISX

FSISX Risk / Return Rank: 37
FSISX Sharpe Ratio Rank: 39
FSISX Sortino Ratio Rank: 38
FSISX Omega Ratio Rank: 39
FSISX Calmar Ratio Rank: 31
FSISX Martin Ratio Rank: 35

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.

AIOIX vs. FSISX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for American Century International Opportunities Fund (AIOIX) and Fidelity SAI International Small Cap Index Fund (FSISX). 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.

	AIOIX	FSISX	Difference
Sharpe ratio: Return per unit of total volatility	1.73	1.82	-0.10
Sortino ratio: Return per unit of downside risk	2.36	2.58	-0.22
Omega ratio: Gain probability vs. loss probability	1.31	1.33	-0.03
Calmar ratio: Return relative to maximum drawdown	2.32	2.10	+0.22
Martin ratio: Return relative to average drawdown	9.33	7.81	+1.52
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

AIOIX vs. FSISX - Sharpe Ratio Comparison

The current AIOIX Sharpe Ratio is 1.73, which is comparable to the FSISX Sharpe Ratio of 1.82. The chart below compares the historical Sharpe Ratios of AIOIX and FSISX, 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

	AIOIX	FSISX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.73	1.82	-0.10
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.16	0.35	-0.20
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.44	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.55	0.36	+0.18

Drawdowns

AIOIX vs. FSISX - Drawdown Comparison

The maximum AIOIX drawdown since its inception was -66.16%, which is greater than FSISX's maximum drawdown of -36.84%. Use the drawdown chart below to compare losses from any high point for AIOIX and FSISX.

Drawdown Indicators

	AIOIX	FSISX	Difference
Max Drawdown Largest peak-to-trough decline	-66.16%	-36.84%	-29.32%
Max Drawdown (1Y) Largest decline over 1 year	-14.00%	-11.73%	-2.27%
Max Drawdown (3Y) Largest decline over 3 years	-18.46%	-14.75%	-3.71%
Max Drawdown (5Y) Largest decline over 5 years	-41.19%	-36.84%	-4.35%
Max Drawdown (10Y) Largest decline over 10 years	-41.19%	—	—
Current Drawdown Current decline from peak	-1.86%	-1.29%	-0.57%
Average Drawdown Average peak-to-trough decline	-16.02%	-13.12%	-2.90%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.47%	3.14%	+0.33%

Volatility

AIOIX vs. FSISX - Volatility Comparison

American Century International Opportunities Fund (AIOIX) has a higher volatility of 6.73% compared to Fidelity SAI International Small Cap Index Fund (FSISX) at 3.73%. This indicates that AIOIX's price experiences larger fluctuations and is considered to be riskier than FSISX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	AIOIX	FSISX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.73%	3.73%	+3.00%
Volatility (6M) Calculated over the trailing 6-month period	16.02%	10.86%	+5.16%
Volatility (1Y) Calculated over the trailing 1-year period	18.86%	13.52%	+5.34%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	18.91%	15.90%	+3.01%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.95%	15.89%	+3.06%

AIOIX vs. FSISX - Expense Ratio Comparison

AIOIX has a 1.48% expense ratio, which is higher than FSISX's 0.10% expense ratio.

Dividends

AIOIX vs. FSISX - Dividend Comparison

AIOIX's dividend yield for the trailing twelve months is around 0.24%, less than FSISX's 3.35% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
AIOIX American Century International Opportunities Fund	0.24%	0.27%	0.32%	0.23%	0.00%	17.80%	3.18%	0.92%	5.28%	9.09%	0.04%	7.15%
FSISX Fidelity SAI International Small Cap Index Fund	3.35%	3.70%	3.33%	3.13%	3.02%	1.30%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both AIOIX and FSISX in my portfolio?

AIOIX and FSISX have a correlation of 0.85, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, AIOIX or FSISX?

AIOIX has higher volatility (6.73%) compared to FSISX (3.73%). In terms of maximum drawdown, AIOIX dropped -66.16% vs FSISX's -36.84%.

Which has better risk-adjusted returns?

FSISX currently has the higher Sharpe Ratio (1.82 vs 1.73), 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.