BIGIX vs. CIGIX

Last updated Jun 23, 2026

BIGIX (William Blair International Growth Fund Class I) and CIGIX (Calamos International Growth Fund) are both Foreign Large Cap Equities funds. Over the past 10 years, BIGIX returned 8.91%/yr vs 10.79%/yr for CIGIX. Their correlation of 0.89 suggests significant overlap in exposure. BIGIX charges 0.90%/yr vs 0.85%/yr for CIGIX.

Performance

BIGIX vs. CIGIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in William Blair International Growth Fund Class I (BIGIX) and Calamos International Growth Fund (CIGIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, BIGIX achieves a 17.77% return, which is significantly lower than CIGIX's 35.71% return. Over the past 10 years, BIGIX has underperformed CIGIX with an annualized return of 8.91%, while CIGIX has yielded a comparatively higher 10.79% annualized return.

BIGIX

• 1D: 1.78%
• 1M: 4.55%
• YTD: 17.77%
• 6M: 18.56%
• 1Y: 27.98%
• 3Y*: 13.26%
• 5Y*: 3.65%
• 10Y*: 8.91%

CIGIX

• 1D: 3.08%
• 1M: 6.28%
• YTD: 35.71%
• 6M: 36.79%
• 1Y: 51.70%
• 3Y*: 24.90%
• 5Y*: 5.46%
• 10Y*: 10.79%

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

BIGIX vs. CIGIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
BIGIX William Blair International Growth Fund Class I	17.77%	18.17%	2.38%	15.43%	-28.46%	8.95%	32.01%	30.66%	-17.71%	29.48%
CIGIX Calamos International Growth Fund	35.71%	23.11%	12.51%	15.33%	-30.54%	-8.98%	44.95%	29.69%	-20.93%	39.54%

Correlation

The correlation between BIGIX and CIGIX is 0.83, 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	0.83
Correlation (3Y) Calculated over the trailing 3-year period	0.84
Correlation (5Y) Calculated over the trailing 5-year period	0.86
Correlation (10Y) Calculated over the trailing 10-year period	0.87
Correlation (All Time) Calculated using the full available price history since Mar 17, 2005	0.89

The correlation between BIGIX and CIGIX has been stable across timeframes, ranging from 0.83 to 0.89 - a consistent structural relationship.

Return for Risk

BIGIX vs. CIGIX — Risk / Return Rank

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

BIGIX

BIGIX Risk / Return Rank: 38
BIGIX Sharpe Ratio Rank: 38
BIGIX Sortino Ratio Rank: 35
BIGIX Omega Ratio Rank: 44
BIGIX Calmar Ratio Rank: 34
BIGIX Martin Ratio Rank: 37

CIGIX

CIGIX Risk / Return Rank: 59
CIGIX Sharpe Ratio Rank: 56
CIGIX Sortino Ratio Rank: 50
CIGIX Omega Ratio Rank: 54
CIGIX Calmar Ratio Rank: 75
CIGIX Martin Ratio Rank: 62

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.

BIGIX vs. CIGIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for William Blair International Growth Fund Class I (BIGIX) and Calamos International Growth Fund (CIGIX). 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.

	BIGIX	CIGIX	Difference
Sharpe ratio: Return per unit of total volatility	1.66	2.03	-0.37
Sortino ratio: Return per unit of downside risk	2.30	2.72	-0.42
Omega ratio: Gain probability vs. loss probability	1.33	1.37	-0.04
Calmar ratio: Return relative to maximum drawdown	2.08	3.21	-1.13
Martin ratio: Return relative to average drawdown	7.75	11.54	-3.79

BIGIX vs. CIGIX - Sharpe Ratio Comparison

The current BIGIX Sharpe Ratio is 1.66, which is comparable to the CIGIX Sharpe Ratio of 2.03. The chart below compares the historical Sharpe Ratios of BIGIX and CIGIX, 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

BIGIX vs. CIGIX - Drawdown Comparison

The maximum BIGIX drawdown since its inception was -65.22%, roughly equal to the maximum CIGIX drawdown of -64.46%. Use the drawdown chart below to compare losses from any high point for BIGIX and CIGIX.

Drawdown Indicators

	BIGIX	CIGIX	Difference
Max Drawdown Largest peak-to-trough decline	-65.22%	-64.46%	-0.76%
Max Drawdown (1Y) Largest decline over 1 year	-13.21%	-15.88%	+2.67%
Max Drawdown (3Y) Largest decline over 3 years	-17.09%	-19.38%	+2.29%
Max Drawdown (5Y) Largest decline over 5 years	-41.03%	-50.15%	+9.12%
Max Drawdown (10Y) Largest decline over 10 years	-41.03%	-50.15%	+9.12%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-17.14%	-15.27%	-1.87%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.53%	4.40%	-0.87%

Volatility

BIGIX vs. CIGIX - Volatility Comparison

The current volatility for William Blair International Growth Fund Class I (BIGIX) is 7.60%, while Calamos International Growth Fund (CIGIX) has a volatility of 12.19%. This indicates that BIGIX experiences smaller price fluctuations and is considered to be less risky than CIGIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BIGIX	CIGIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	7.60%	12.19%	-4.59%
Volatility (6M) Calculated over the trailing 6-month period	14.57%	22.20%	-7.63%
Volatility (1Y) Calculated over the trailing 1-year period	16.52%	25.03%	-8.51%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.98%	21.58%	-4.60%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	17.33%	20.23%	-2.90%

BIGIX vs. CIGIX - Expense Ratio Comparison

BIGIX has a 0.90% expense ratio, which is higher than CIGIX's 0.85% expense ratio.

Dividends

BIGIX vs. CIGIX - Dividend Comparison

BIGIX's dividend yield for the trailing twelve months is around 15.67%, more than CIGIX's 9.94% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BIGIX William Blair International Growth Fund Class I	15.67%	18.45%	7.49%	3.52%	7.84%	11.41%	1.11%	1.29%	9.05%	1.54%	1.80%	1.18%
CIGIX Calamos International Growth Fund	9.94%	13.49%	4.54%	0.28%	0.00%	0.33%	5.42%	0.00%	13.25%	3.76%	0.00%	0.13%

Frequently Asked Questions

Can I hold both BIGIX and CIGIX in my portfolio?

BIGIX and CIGIX have a correlation of 0.83, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, BIGIX or CIGIX?

CIGIX has higher volatility (12.19%) compared to BIGIX (7.60%). In terms of maximum drawdown, BIGIX dropped -65.22% vs CIGIX's -64.46%.

Which has better risk-adjusted returns?

CIGIX currently has the higher Sharpe Ratio (2.03 vs 1.66), 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.