MIAIX vs. FFNYX

Last updated Jun 3, 2026

MIAIX (MFS Inflation-Adjusted Bond Fund) and FFNYX (Fidelity SAI 0-5 Year Inflation-Protected Bond Index Fund) are both Inflation-Protected Bonds funds. A 0.68 correlation means they provide meaningful diversification when combined. MIAIX charges 0.49%/yr vs 0.05%/yr for FFNYX.

Performance

MIAIX vs. FFNYX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in MFS Inflation-Adjusted Bond Fund (MIAIX) and Fidelity SAI 0-5 Year Inflation-Protected Bond Index Fund (FFNYX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

MIAIX

• 1D: -0.11%
• 1M: -0.22%
• YTD: 1.33%
• 6M: 1.00%
• 1Y: 4.47%
• 3Y*: 3.21%
• 5Y*: 0.38%
• 10Y*: 2.07%

FFNYX

• 1D: 0.00%
• 1M: -0.00%
• YTD: —
• 6M: —
• 1Y: —
• 3Y*: —
• 5Y*: —
• 10Y*: —

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

MIAIX vs. FFNYX - Yearly Performance Comparison

	2026 (YTD)
MIAIX MFS Inflation-Adjusted Bond Fund	0.44%
FFNYX Fidelity SAI 0-5 Year Inflation-Protected Bond Index Fund	0.93%

Correlation

The correlation between MIAIX and FFNYX is 0.68, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (All Time) Calculated using the full available price history since Mar 17, 2026	0.68

Return for Risk

MIAIX vs. FFNYX — Risk / Return Rank

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

MIAIX

MIAIX Risk / Return Rank: 21
MIAIX Sharpe Ratio Rank: 17
MIAIX Sortino Ratio Rank: 18
MIAIX Omega Ratio Rank: 16
MIAIX Calmar Ratio Rank: 30
MIAIX Martin Ratio Rank: 24

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.

MIAIX vs. FFNYX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for MFS Inflation-Adjusted Bond Fund (MIAIX) and Fidelity SAI 0-5 Year Inflation-Protected Bond Index Fund (FFNYX). 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.

	MIAIX	FFNYX	Difference
Sharpe ratio Return per unit of total volatility	1.18	—	—
Sortino ratio Return per unit of downside risk	1.81	—	—
Omega ratio Gain probability vs. loss probability	1.21	—	—
Calmar ratio Return relative to maximum drawdown	2.05	—	—
Martin ratio Return relative to average drawdown	6.14	—	—
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

Sharpe Ratios by Period

	MIAIX	FFNYX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.18	—	—
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.06	—	—
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.38	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.49	2.37	-1.88

Drawdowns

MIAIX vs. FFNYX - Drawdown Comparison

The maximum MIAIX drawdown since its inception was -15.99%, which is greater than FFNYX's maximum drawdown of -0.69%. Use the drawdown chart below to compare losses from any high point for MIAIX and FFNYX.

Drawdown Indicators

	MIAIX	FFNYX	Difference
Max Drawdown Largest peak-to-trough decline	-15.99%	-0.69%	-15.30%
Max Drawdown (1Y) Largest decline over 1 year	-2.18%	—	—
Max Drawdown (3Y) Largest decline over 3 years	-5.64%	—	—
Max Drawdown (5Y) Largest decline over 5 years	-15.99%	—	—
Max Drawdown (10Y) Largest decline over 10 years	-15.99%	—	—
Current Drawdown Current decline from peak	-2.32%	-0.10%	-2.22%
Average Drawdown Average peak-to-trough decline	-4.25%	-0.18%	-4.07%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.73%	—	—

Volatility

Volatility by Period

	MIAIX	FFNYX	Difference
Volatility (1M) Calculated over the trailing 1-month period	1.00%	—	—
Volatility (6M) Calculated over the trailing 6-month period	2.42%	—	—
Volatility (1Y) Calculated over the trailing 1-year period	3.53%	1.89%	+1.64%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	6.18%	1.89%	+4.29%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	5.49%	1.89%	+3.60%

MIAIX vs. FFNYX - Expense Ratio Comparison

MIAIX has a 0.49% expense ratio, which is higher than FFNYX's 0.05% expense ratio.

Dividends

MIAIX vs. FFNYX - Dividend Comparison

MIAIX's dividend yield for the trailing twelve months is around 4.05%, more than FFNYX's 0.04% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FFNYX Fidelity SAI 0-5 Year Inflation-Protected Bond Index Fund	0.04%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
MIAIX MFS Inflation-Adjusted Bond Fund	4.05%	4.10%	4.10%	4.00%	7.96%	5.10%	1.45%	2.18%	2.85%	2.14%	1.82%	0.67%

Frequently Asked Questions

Can I hold both MIAIX and FFNYX in my portfolio?

MIAIX and FFNYX have a correlation of 0.68, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.