MWNIX vs. COIIX

Last updated Aug 1, 2026

MWNIX (MFS International New Discovery Fund) and COIIX (Calvert International Opportunities Fund) are both Foreign Small & Mid Cap Equities funds. Over the past 10 years, MWNIX returned 6.38%/yr vs 7.19%/yr for COIIX. Their correlation of 0.91 means they have usually moved in the same direction. MWNIX charges 1.03%/yr vs 1.06%/yr for COIIX.

Performance

MWNIX vs. COIIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS International New Discovery Fund (MWNIX) and Calvert International Opportunities Fund (COIIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, MWNIX achieves a 8.70% return, which is significantly lower than COIIX's 9.63% return. Over the past 10 years, MWNIX has underperformed COIIX with an annualized return of 6.38%, while COIIX has yielded a comparatively higher 7.19% annualized return.

MWNIX

• 1D: 2.01%
• 1M: 1.55%
• 6M: 4.96%
• YTD: 8.70%
• 1Y: 11.50%
• 3Y*: 9.49%
• 5Y*: 3.12%
• 10Y*: 6.38%
• ALL TIME*: 9.52%

COIIX

• 1D: 1.82%
• 1M: 3.05%
• 6M: 6.58%
• YTD: 9.63%
• 1Y: 11.95%
• 3Y*: 8.04%
• 5Y*: 0.64%
• 10Y*: 7.19%
• ALL TIME*: 4.51%

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

Liquidity Comparison

Position	Avg. Volume Value (2W)	Avg. Volume Value (1M)	Avg. Volume Value (3M)
COIIX Calvert International Opportunities Fund	$0.00	$0.00	$0.00
MWNIX MFS International New Discovery Fund	$0.00	$0.00	$0.00

MWNIX vs. COIIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
MWNIX MFS International New Discovery Fund	8.70%	16.88%	0.90%	13.03%	-18.63%	5.06%	9.98%	22.85%	-10.41%	30.67%
COIIX Calvert International Opportunities Fund	9.63%	13.80%	-1.48%	12.95%	-26.69%	13.97%	14.05%	26.09%	-14.57%	38.55%

Correlation

The correlation between MWNIX and COIIX is 0.91, meaning they have usually moved in the same direction, including during past declines.

	Correlation
Correlation (1Y) Focuses on recent behavior, but can change the most.	0.91
Correlation (3Y) Balances recent behavior with more history.	0.92
Correlation (5Y) Shows whether the relationship held over a longer period.	0.94
Correlation (10Y) Provides a long-term view across more market conditions.	0.92
Correlation (All Time) Calculated using the full available price history since May 31, 2007	0.91

The correlation between MWNIX and COIIX has been stable across timeframes, ranging from 0.91 to 0.94 - a consistent structural relationship.

Return for Risk

MWNIX vs. COIIX — Risk / Return Rank

Compare historical risk-adjusted metric ranks over the past 12 months.

MWNIX

MWNIX Risk / Return Rank: 24
MWNIX Sharpe Ratio Rank: 25
MWNIX Sortino Ratio Rank: 26
MWNIX Omega Ratio Rank: 26
MWNIX Calmar Ratio Rank: 19
MWNIX Martin Ratio Rank: 22

COIIX

COIIX Risk / Return Rank: 23
COIIX Sharpe Ratio Rank: 23
COIIX Sortino Ratio Rank: 24
COIIX Omega Ratio Rank: 24
COIIX Calmar Ratio Rank: 19
COIIX Martin Ratio Rank: 23

The rank (0–100) uses a weighted average of the Sharpe, Sortino, Omega, Calmar, and Martin percentile ranks for the trailing 12 months. Higher means stronger historical risk-adjusted performance within the peer group.

MWNIX vs. COIIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS International New Discovery Fund (MWNIX) and Calvert International Opportunities Fund (COIIX). 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.

	MWNIX	COIIX	Difference
Sharpe ratio: Return per unit of total volatility	0.90	0.84	+0.06
Sortino ratio: Return per unit of downside risk	1.35	1.29	+0.06
Omega ratio: Gain probability vs. loss probability	1.17	1.16	+0.01
Calmar ratio: Return relative to maximum drawdown	0.96	0.92	+0.03
Martin ratio: Return relative to average drawdown	3.17	3.23	-0.06

MWNIX vs. COIIX - Sharpe Ratio Comparison

The current MWNIX Sharpe Ratio is 0.90, which is comparable to the COIIX Sharpe Ratio of 0.84. The chart below compares the historical Sharpe Ratios of MWNIX and COIIX, 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

MWNIX vs. COIIX - Drawdown Comparison

The maximum MWNIX drawdown since its inception was -58.38%, roughly equal to the maximum COIIX drawdown of -57.27%. Use the drawdown chart below to compare losses from any high point for MWNIX and COIIX.

Drawdown Indicators

	MWNIX	COIIX	Difference
Max Drawdown Largest peak-to-trough decline	-58.38%	-57.27%	-1.11%
Max Drawdown (1Y) Largest decline over 1 year	-11.78%	-12.74%	+0.96%
Max Drawdown (3Y) Largest decline over 3 years	-15.12%	-16.54%	+1.42%
Max Drawdown (5Y) Largest decline over 5 years	-33.67%	-40.36%	+6.69%
Max Drawdown (10Y) Largest decline over 10 years	-34.72%	-40.36%	+5.64%
Current Drawdown Current decline from peak	-0.05%	-1.88%	+1.83%
Average Drawdown Average peak-to-trough decline	-9.53%	-14.90%	+5.37%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.54%	3.63%	-0.09%

Volatility

MWNIX vs. COIIX - Volatility Comparison

The current volatility for MFS International New Discovery Fund (MWNIX) is 3.83%, while Calvert International Opportunities Fund (COIIX) has a volatility of 4.04%. This indicates that MWNIX experiences smaller price fluctuations and is considered to be less risky than COIIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	MWNIX	COIIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	3.83%	4.04%	-0.21%
Volatility (6M) Calculated over the trailing 6-month period	10.86%	11.80%	-0.94%
Volatility (1Y) Calculated over the trailing 1-year period	12.50%	14.10%	-1.60%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	13.34%	17.01%	-3.67%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	13.73%	16.68%	-2.95%

MWNIX vs. COIIX - Expense Ratio Comparison

MWNIX has a 1.03% expense ratio, which is lower than COIIX's 1.06% expense ratio.

Dividends

MWNIX vs. COIIX - Dividend Comparison

MWNIX's dividend yield for the trailing twelve months is around 2.98%, less than COIIX's 3.18% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
COIIX Calvert International Opportunities Fund	3.18%	3.49%	3.24%	1.77%	0.61%	7.67%	0.78%	1.32%	9.82%	7.19%	1.52%	4.53%
MWNIX MFS International New Discovery Fund	2.98%	3.24%	7.61%	4.05%	5.68%	5.06%	3.90%	2.67%	6.68%	1.63%	1.09%	1.12%

Frequently Asked Questions

Can I hold both MWNIX and COIIX in my portfolio?

With a correlation of 0.91, MWNIX and COIIX 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, MWNIX or COIIX?

COIIX has higher volatility (4.04%) compared to MWNIX (3.83%). In terms of maximum drawdown, MWNIX dropped -58.38% vs COIIX's -57.27%.

Which has better risk-adjusted returns?

MWNIX currently has the higher Sharpe Ratio (0.90 vs 0.84), 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.