TSSIX vs. THDIX

Last updated Jun 4, 2026

TSSIX (Thornburg Strategic Municipal Income Fund) and THDIX (Thornburg Developing World Fund) are both mutual funds - TSSIX is a Municipal Bonds fund managed by Thornburg, while THDIX is a Emerging Markets Diversified fund managed by Thornburg. Over the past 10 years, TSSIX returned 2.18%/yr vs 9.29%/yr for THDIX. At a correlation of -0.05, they often move in opposite directions. TSSIX charges 0.59%/yr vs 1.06%/yr for THDIX.

Performance

TSSIX vs. THDIX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Thornburg Strategic Municipal Income Fund (TSSIX) and Thornburg Developing World Fund (THDIX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TSSIX achieves a 1.92% return, which is significantly lower than THDIX's 27.57% return. Over the past 10 years, TSSIX has underperformed THDIX with an annualized return of 2.18%, while THDIX has yielded a comparatively higher 9.29% annualized return.

TSSIX

• 1D: 0.21%
• 1M: 0.79%
• YTD: 1.92%
• 6M: 1.98%
• 1Y: 6.60%
• 3Y*: 5.11%
• 5Y*: 1.65%
• 10Y*: 2.18%

THDIX

• 1D: 0.91%
• 1M: 8.91%
• YTD: 27.57%
• 6M: 31.97%
• 1Y: 50.49%
• 3Y*: 21.15%
• 5Y*: 4.79%
• 10Y*: 9.29%

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

TSSIX vs. THDIX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
TSSIX Thornburg Strategic Municipal Income Fund	1.92%	5.62%	3.77%	5.51%	-8.30%	1.50%	4.03%	5.99%	1.04%	4.21%
THDIX Thornburg Developing World Fund	27.57%	27.84%	5.80%	6.61%	-25.52%	-2.67%	22.98%	29.95%	-14.88%	35.86%

Correlation

The correlation between TSSIX and THDIX is 0.14, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.14
Correlation (3Y) Calculated over the trailing 3-year period	0.09
Correlation (5Y) Calculated over the trailing 5-year period	0.10
Correlation (10Y) Calculated over the trailing 10-year period	0.02
Correlation (All Time) Calculated using the full available price history since Jan 5, 2010	-0.05

The correlation between TSSIX and THDIX shifts across timeframes, from -0.05 (all time) to 0.14 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

TSSIX vs. THDIX — Risk / Return Rank

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

TSSIX

TSSIX Risk / Return Rank: 70
TSSIX Sharpe Ratio Rank: 77
TSSIX Sortino Ratio Rank: 87
TSSIX Omega Ratio Rank: 92
TSSIX Calmar Ratio Rank: 48
TSSIX Martin Ratio Rank: 47

THDIX

THDIX Risk / Return Rank: 87
THDIX Sharpe Ratio Rank: 92
THDIX Sortino Ratio Rank: 86
THDIX Omega Ratio Rank: 82
THDIX Calmar Ratio Rank: 88
THDIX Martin Ratio Rank: 87

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.

TSSIX vs. THDIX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Thornburg Strategic Municipal Income Fund (TSSIX) and Thornburg Developing World Fund (THDIX). 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.

	TSSIX	THDIX	Difference
Sharpe ratio: Return per unit of total volatility	2.54	3.10	-0.56
Sortino ratio: Return per unit of downside risk	4.17	4.10	+0.06
Omega ratio: Gain probability vs. loss probability	1.68	1.54	+0.14
Calmar ratio: Return relative to maximum drawdown	2.63	4.35	-1.72
Martin ratio: Return relative to average drawdown	9.78	16.72	-6.94
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

TSSIX vs. THDIX - Sharpe Ratio Comparison

The current TSSIX Sharpe Ratio is 2.54, which is comparable to the THDIX Sharpe Ratio of 3.10. The chart below compares the historical Sharpe Ratios of TSSIX and THDIX, 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

	TSSIX	THDIX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.54	3.10	-0.56
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.46	0.29	+0.17
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.63	0.54	+0.08
Sharpe Ratio (All Time) Calculated using the full available price history	1.34	0.46	+0.87

Drawdowns

TSSIX vs. THDIX - Drawdown Comparison

The maximum TSSIX drawdown since its inception was -12.64%, smaller than the maximum THDIX drawdown of -44.31%. Use the drawdown chart below to compare losses from any high point for TSSIX and THDIX.

Drawdown Indicators

	TSSIX	THDIX	Difference
Max Drawdown Largest peak-to-trough decline	-12.64%	-44.31%	+31.67%
Max Drawdown (1Y) Largest decline over 1 year	-2.46%	-11.76%	+9.30%
Max Drawdown (3Y) Largest decline over 3 years	-4.67%	-16.09%	+11.42%
Max Drawdown (5Y) Largest decline over 5 years	-12.64%	-40.70%	+28.06%
Max Drawdown (10Y) Largest decline over 10 years	-12.64%	-44.31%	+31.67%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-1.98%	-13.44%	+11.46%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.66%	3.05%	-2.39%

Volatility

TSSIX vs. THDIX - Volatility Comparison

The current volatility for Thornburg Strategic Municipal Income Fund (TSSIX) is 0.91%, while Thornburg Developing World Fund (THDIX) has a volatility of 5.79%. This indicates that TSSIX experiences smaller price fluctuations and is considered to be less risky than THDIX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TSSIX	THDIX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.91%	5.79%	-4.88%
Volatility (6M) Calculated over the trailing 6-month period	1.85%	13.42%	-11.57%
Volatility (1Y) Calculated over the trailing 1-year period	2.55%	16.47%	-13.92%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	3.62%	16.64%	-13.02%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	3.48%	17.11%	-13.63%

TSSIX vs. THDIX - Expense Ratio Comparison

TSSIX has a 0.59% expense ratio, which is lower than THDIX's 1.06% expense ratio.

Dividends

TSSIX vs. THDIX - Dividend Comparison

TSSIX's dividend yield for the trailing twelve months is around 4.13%, more than THDIX's 2.76% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
THDIX Thornburg Developing World Fund	2.76%	3.52%	2.90%	2.05%	1.77%	0.00%	0.15%	1.52%	1.31%	0.74%	0.55%	0.69%
TSSIX Thornburg Strategic Municipal Income Fund	4.13%	5.27%	4.42%	2.86%	2.48%	2.08%	2.61%	2.95%	2.76%	2.65%	2.40%	2.63%

Frequently Asked Questions

Can I hold both TSSIX and THDIX in my portfolio?

TSSIX and THDIX have a correlation of 0.14, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, TSSIX or THDIX?

THDIX has higher volatility (5.79%) compared to TSSIX (0.91%). In terms of maximum drawdown, TSSIX dropped -12.64% vs THDIX's -44.31%.

Which has better risk-adjusted returns?

THDIX currently has the higher Sharpe Ratio (3.10 vs 2.54), 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.