SIBSX Performance — MFS Moderate Allocation Portfolio, Service Class
Data updated: 2026-08-24
SIBSX returned +4.76% year to date and +8.48% over one year to Jun 2026. Annualised returns are +9.79% over 3 years and +4.20% over 5 years. The fund trailed its US Multi-Cap Blend category average: $100 invested three years ago grew to $132, against $143 for the category, and to $108 over one year, against $116. Volatility over the past three years was 8.82% a year. In the 12 months to Jun 2026 the fund lost a net $54.1M, and assets reached $822.90M.
SIBSX Growth of $100
What $100 invested in MFS Moderate Allocation Portfolio grew to, compounded from monthly returns reported on SEC Form N-PORT, against the US Multi-Cap Blend category average over the same months.
| Period | SIBSX | Category average |
|---|---|---|
| 1 year (Jul 2025 – Jun 2026) | $108 | $116 |
| 3 years (Jul 2023 – Jun 2026) | $132 | $143 |
| 5 years (Jul 2021 – Jun 2026) | $123 | $136 |
| Since data start (Jul 2019 – Jun 2026) | $158 | $173 |
SIBSX Trailing Returns
Total returns to Jun 2026, from SEC N-PORT.
| Period | Total return |
|---|---|
| YTD | +4.76% |
| 1 year | +8.48% |
| 3 years (annualised) | +9.79% |
| 5 years (annualised) | +4.20% |
SIBSX Annual Returns
Calendar-year total returns of MFS Moderate Allocation Portfolio, compounded from monthly SEC N-PORT returns. Partial years show the months covered.
| Year | Total return |
|---|---|
| 2026 (Jan–Jun) | +4.76% |
| 2025 | +10.95% |
| 2024 | +8.13% |
| 2023 | +12.63% |
| 2022 | −16.92% |
| 2021 | +11.26% |
| 2020 | +14.08% |
| 2019 (Jul–Dec) | +5.93% |
SIBSX 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 | +1.7% | +1.6% | −4.8% | +4.6% | +1.0% | +0.9% | — | — | — | — | — | — |
| 2025 | +2.6% | 0.0% | −2.4% | +0.8% | +3.1% | +2.9% | −0.1% | +1.7% | +1.1% | +0.1% | +0.6% | +0.1% |
| 2024 | 0.0% | +2.3% | +2.4% | −3.5% | +2.9% | +0.5% | +2.7% | +2.0% | +1.2% | −2.2% | +3.0% | −3.3% |
| 2023 | +5.3% | −3.0% | +2.0% | +1.0% | −1.6% | +3.3% | +1.7% | −1.6% | −4.0% | −2.0% | +6.9% | +4.7% |
| 2022 | −4.9% | −2.0% | −0.3% | −6.0% | +0.3% | −5.8% | +5.9% | −4.1% | −7.2% | +3.7% | +5.9% | −2.7% |
| 2021 | −1.2% | +0.9% | +1.6% | +3.5% | +0.9% | +0.8% | +1.8% | +1.5% | −3.1% | +3.3% | −1.5% | +2.4% |
| 2020 | +0.8% | −4.1% | −9.2% | +7.4% | +4.0% | +1.6% | +4.1% | +2.8% | −1.4% | −1.4% | +7.0% | +3.0% |
| 2019 | — | — | — | — | — | — | +0.5% | +0.4% | +0.5% | +1.1% | +1.7% | +1.6% |
SIBSX Risk
Risk measures from monthly returns over Jul 2023 – Jun 2026.
- 3-year volatility (annualised): 8.82%
- 3-year Sharpe ratio: 0.60 (vs 4.5% risk-free rate)
- Best month: +6.88% (Nov 2023)
- Worst month: −4.79% (Mar 2026)
SIBSX Fund Flows
Monthly money in and out of MFS Moderate Allocation Portfolio, from SEC Form N-PORT.
- 12-month net flow: −$54.1M
- 12-month gross sales (incl. reinvestments): $92.9M
- Sales ÷ redemptions: 0.63×
| Month | Sales | Redemptions | Net flow |
|---|---|---|---|
| Jun 2026 | $618K | $11.8M | −$11.2M |
| May 2026 | $9.6M | $12.4M | −$2.9M |
| Apr 2026 | $85K | $13.1M | −$13.0M |
| Mar 2026 | $1.8M | $13.5M | −$11.7M |
| Feb 2026 | $94K | $10.1M | −$10.0M |
| Jan 2026 | $57K | $10.1M | −$10.0M |
| Dec 2025 | $2.4M | $11.4M | −$9.0M |
| Nov 2025 | $59K | $11.8M | −$11.7M |
| Oct 2025 | $39K | $15.1M | −$15.1M |
| Sep 2025 | $1.6M | $13.0M | −$11.5M |
| Aug 2025 | $76.6M | $14.3M | $62.3M |
| Jul 2025 | $46K | $10.2M | −$10.2M |
SIBSX Assets Under Management
Net assets of MFS Moderate Allocation Portfolio by report date, from SEC N-PORT filings.
| Report date | Net assets |
|---|---|
| 2026-06-30 | $822.90M |
| 2026-03-31 | $797.88M |
| 2025-12-31 | $843.07M |
| 2025-09-30 | $872.12M |
| 2025-06-30 | $884.65M |
| 2025-03-31 | $860.15M |
| 2024-12-31 | $895.74M |
| 2024-09-30 | $962.47M |
| 2024-06-30 | $950.00M |
| 2024-03-31 | $993.67M |
| 2023-12-31 | $990.63M |
| 2023-09-30 | $939.56M |
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.