MIAIX Performance — MFS Inflation-Adjusted Bond Fund, Class I
Data updated: 2026-09-24
MIAIX returned +0.03% year to date and +1.80% over one year to Jul 2026. Annualised returns are +3.01% over 3 years and −0.34% over 5 years. The fund trailed its Intermediate Government Bond category average: $100 invested three years ago grew to $109, against $111 for the category, and to $102 over one year, against $103. Volatility over the past three years was 4.65% a year. In the 12 months to Jul 2026 the fund lost a net $13.1M, and assets reached $1.49B.
MIAIX Growth of $100
What $100 invested in MFS Inflation-Adjusted Bond Fund grew to, compounded from monthly returns reported on SEC Form N-PORT, against the Intermediate Government Bond category average over the same months.
| Period | MIAIX | Category average |
|---|---|---|
| 1 year (Aug 2025 – Jul 2026) | $102 | $103 |
| 3 years (Aug 2023 – Jul 2026) | $109 | $111 |
| 5 years (Aug 2021 – Jul 2026) | $98 | $101 |
| Since data start (Aug 2019 – Jul 2026) | $114 | $112 |
MIAIX Trailing Returns
Total returns to Jul 2026, from SEC N-PORT.
| Period | Total return |
|---|---|
| YTD | +0.03% |
| 1 year | +1.80% |
| 3 years (annualised) | +3.01% |
| 5 years (annualised) | −0.34% |
MIAIX Annual Returns
Calendar-year total returns of MFS Inflation-Adjusted Bond Fund, compounded from monthly SEC N-PORT returns. Partial years show the months covered.
| Year | Total return |
|---|---|
| 2026 (Jan–Jul) | +0.03% |
| 2025 | +6.30% |
| 2024 | +1.66% |
| 2023 | +2.12% |
| 2022 | −11.86% |
| 2021 | +4.64% |
| 2020 | +10.56% |
| 2019 (Aug–Dec) | +1.40% |
MIAIX Monthly Returns
Monthly total returns as reported on SEC Form N-PORT.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | +0.4% | +1.3% | −1.5% | +1.0% | +0.2% | −0.6% | −0.8% | — | — | — | — | — |
| 2025 | +1.2% | +2.2% | +0.7% | 0.0% | −0.8% | +1.0% | 0.0% | +1.8% | +0.2% | +0.2% | +0.2% | −0.7% |
| 2024 | +0.4% | −1.3% | +0.8% | −1.6% | +1.7% | +0.6% | +1.9% | +0.8% | +1.5% | −1.9% | +0.4% | −1.6% |
| 2023 | +1.9% | −1.4% | +2.7% | +0.1% | −1.7% | −0.8% | +0.1% | −1.2% | −2.4% | −1.0% | +3.1% | +2.8% |
| 2022 | −2.2% | +0.9% | −1.8% | −2.2% | −0.9% | −3.1% | +4.2% | −2.8% | −6.2% | +1.1% | +1.9% | −1.0% |
| 2021 | +0.3% | −2.1% | +0.2% | +1.4% | +0.9% | +0.6% | +2.3% | −0.2% | −0.7% | +0.9% | +0.9% | +0.1% |
| 2020 | +2.3% | +1.5% | −2.0% | +2.8% | +0.2% | +1.1% | +2.5% | +0.6% | 0.0% | −0.7% | +1.0% | +0.9% |
| 2019 | — | — | — | — | — | — | — | +2.7% | −1.6% | +0.2% | 0.0% | +0.1% |
MIAIX Risk
Risk measures from monthly returns over Aug 2023 – Jul 2026.
- 3-year volatility (annualised): 4.65%
- 3-year Sharpe ratio: -0.32 (vs 4.5% risk-free rate)
- Best month: +3.11% (Nov 2023)
- Worst month: −2.40% (Sep 2023)
MIAIX Fund Flows
Monthly money in and out of MFS Inflation-Adjusted Bond Fund, from SEC Form N-PORT.
- 12-month net flow: −$13.1M
- 12-month gross sales (incl. reinvestments): $124.0M
- Sales ÷ redemptions: 0.90×
| Month | Sales | Redemptions | Net flow |
|---|---|---|---|
| Jul 2026 | $11.8M | $10.3M | $1.5M |
| Jun 2026 | $29.7M | $5.0M | $24.8M |
| May 2026 | $4.9M | $6.7M | −$1.8M |
| Apr 2026 | $3.8M | $7.8M | −$4.0M |
| Mar 2026 | $2.1M | $35.8M | −$33.7M |
| Feb 2026 | $7.5M | $10.1M | −$2.7M |
| Jan 2026 | $4.2M | $6.6M | −$2.4M |
| Dec 2025 | $29.9M | $4.7M | $25.2M |
| Nov 2025 | $1.2M | $24.4M | −$23.2M |
| Oct 2025 | $2.4M | $7.7M | −$5.3M |
| Sep 2025 | $24.4M | $7.9M | $16.5M |
| Aug 2025 | $2.0M | $10.1M | −$8.0M |
MIAIX Assets Under Management
Net assets of MFS Inflation-Adjusted Bond Fund by report date, from SEC N-PORT filings.
| Report date | Net assets |
|---|---|
| 2026-07-31 | $1.49B |
| 2026-04-30 | $1.51B |
| 2026-01-31 | $1.54B |
| 2025-10-31 | $1.56B |
| 2025-07-31 | $1.54B |
| 2025-04-30 | $1.45B |
| 2025-01-31 | $1.52B |
| 2024-10-31 | $1.52B |
| 2024-07-31 | $1.53B |
| 2024-04-30 | $1.49B |
| 2024-01-31 | $1.52B |
| 2023-10-31 | $1.42B |
For information only. Not investment advice: figures are as reported in SEC filings and may contain errors or be out of date. Past performance does not guarantee future results.