TANDX vs. FZILX

Last updated Jul 14, 2026

TANDX (Castle Tandem Fund) and FZILX (Fidelity ZERO International Index Fund) are both mutual funds - TANDX is a Large Cap Blend Equities fund managed by Castle Investment Management, while FZILX is a Foreign Large Cap Equities fund tracking the Fidelity Global ex U.S. Index. Over the past 5 years, TANDX returned 1.80%/yr vs 9.32%/yr for FZILX. A 0.59 correlation means they provide meaningful diversification when combined. TANDX charges 1.59%/yr vs 0.00%/yr for FZILX.

Performance

TANDX vs. FZILX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Castle Tandem Fund (TANDX) and Fidelity ZERO International Index Fund (FZILX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, TANDX achieves a -10.08% return, which is significantly lower than FZILX's 14.53% return.

TANDX

• 1D: 0.06%
• 1M: 2.43%
• 6M: -11.19%
• YTD: -10.08%
• 1Y: -12.04%
• 3Y*: 1.61%
• 5Y*: 1.80%
• 10Y*: —

FZILX

• 1D: 0.42%
• 1M: 0.06%
• 6M: 10.12%
• YTD: 14.53%
• 1Y: 28.62%
• 3Y*: 19.56%
• 5Y*: 9.32%
• 10Y*: —

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

TANDX vs. FZILX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
TANDX Castle Tandem Fund	-10.08%	3.67%	7.66%	8.42%	-7.87%	19.03%	13.39%	12.57%
FZILX Fidelity ZERO International Index Fund	14.53%	33.52%	5.32%	16.28%	-15.96%	8.19%	11.06%	9.35%

Correlation

The correlation between TANDX and FZILX is 0.30, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.30
Correlation (3Y) Calculated over the trailing 3-year period	0.43
Correlation (5Y) Calculated over the trailing 5-year period	0.54
Correlation (All Time) Calculated using the full available price history since Mar 22, 2019	0.59

Over the past year, the correlation between TANDX and FZILX has dropped to 0.30 - well below their long-term average of 0.59, suggesting their price drivers have been diverging.

Return for Risk

TANDX vs. FZILX — Risk / Return Rank

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

TANDX

TANDX Risk / Return Rank: 0
TANDX Sharpe Ratio Rank: 0
TANDX Sortino Ratio Rank: 0
TANDX Omega Ratio Rank: 0
TANDX Calmar Ratio Rank: 1
TANDX Martin Ratio Rank: 0

FZILX

FZILX Risk / Return Rank: 61
FZILX Sharpe Ratio Rank: 61
FZILX Sortino Ratio Rank: 56
FZILX Omega Ratio Rank: 63
FZILX Calmar Ratio Rank: 65
FZILX 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.

TANDX vs. FZILX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Castle Tandem Fund (TANDX) and Fidelity ZERO International Index Fund (FZILX). 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.

	TANDX	FZILX	Difference
Sharpe ratio: Return per unit of total volatility	-1.28	1.74	-3.02
Sortino ratio: Return per unit of downside risk	-1.74	2.38	-4.12
Omega ratio: Gain probability vs. loss probability	0.80	1.33	-0.52
Calmar ratio: Return relative to maximum drawdown	-0.76	2.48	-3.24
Martin ratio: Return relative to average drawdown	-1.53	9.43	-10.96

TANDX vs. FZILX - Sharpe Ratio Comparison

The current TANDX Sharpe Ratio is -1.28, which is lower than the FZILX Sharpe Ratio of 1.74. The chart below compares the historical Sharpe Ratios of TANDX and FZILX, 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

TANDX vs. FZILX - Drawdown Comparison

The maximum TANDX drawdown since its inception was -93.98%, which is greater than FZILX's maximum drawdown of -34.37%. Use the drawdown chart below to compare losses from any high point for TANDX and FZILX.

Drawdown Indicators

	TANDX	FZILX	Difference
Max Drawdown Largest peak-to-trough decline	-93.98%	-34.37%	-59.61%
Max Drawdown (1Y) Largest decline over 1 year	-16.88%	-11.24%	-5.64%
Max Drawdown (3Y) Largest decline over 3 years	-93.98%	-13.47%	-80.51%
Max Drawdown (5Y) Largest decline over 5 years	-93.98%	-29.87%	-64.11%
Current Drawdown Current decline from peak	-93.71%	-1.75%	-91.96%
Average Drawdown Average peak-to-trough decline	-21.29%	-6.63%	-14.66%
Ulcer Index Depth and duration of drawdowns from previous peaks	8.35%	2.96%	+5.39%

Volatility

TANDX vs. FZILX - Volatility Comparison

The current volatility for Castle Tandem Fund (TANDX) is 4.02%, while Fidelity ZERO International Index Fund (FZILX) has a volatility of 6.22%. This indicates that TANDX experiences smaller price fluctuations and is considered to be less risky than FZILX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	TANDX	FZILX	Difference
Volatility (1M) Calculated over the trailing 1-month period	4.02%	6.22%	-2.20%
Volatility (6M) Calculated over the trailing 6-month period	8.04%	14.04%	-6.00%
Volatility (1Y) Calculated over the trailing 1-year period	10.01%	16.01%	-6.00%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	595.81%	15.79%	+580.02%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	493.02%	17.40%	+475.62%

TANDX vs. FZILX - Expense Ratio Comparison

TANDX has a 1.59% expense ratio, which is higher than FZILX's 0.00% expense ratio.

Dividends

TANDX vs. FZILX - Dividend Comparison

TANDX's dividend yield for the trailing twelve months is around 6.86%, more than FZILX's 2.34% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018
FZILX Fidelity ZERO International Index Fund	2.34%	2.67%	3.00%	2.98%	2.71%	2.61%	1.64%	2.37%	0.02%
TANDX Castle Tandem Fund	6.86%	6.17%	3.71%	2.10%	1.48%	4.57%	0.33%	0.37%	0.00%

Frequently Asked Questions

Can I hold both TANDX and FZILX in my portfolio?

TANDX and FZILX have a correlation of 0.30, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, TANDX or FZILX?

FZILX has higher volatility (6.22%) compared to TANDX (4.02%). In terms of maximum drawdown, TANDX dropped -93.98% vs FZILX's -34.37%.

Which has better risk-adjusted returns?

FZILX currently has the higher Sharpe Ratio (1.74 vs -1.28), 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.