MUSBX Performance — MFS Blended Research Core Equity Fund, Class B
Data updated: 2026-08-24
MUSBX returned +9.92% year to date and +19.58% over one year to Jun 2026. Annualised returns are +19.36% over 3 years and +12.64% over 5 years. The fund beat its US Large Blend category average: $100 invested three years ago grew to $170, against $157 for the category, and to $120 over one year, against $118. Volatility over the past three years was 12.89% a year. In the 12 months to Jun 2026 the fund lost a net $320.1M, and assets reached $1.41B.
MUSBX Growth of $100
What $100 invested in MFS Blended Research Core Equity Fund grew to, compounded from monthly returns reported on SEC Form N-PORT, against the US Large Blend category average over the same months.
| Period | MUSBX | Category average |
|---|---|---|
| 1 year (Jul 2025 – Jun 2026) | $120 | $118 |
| 3 years (Jul 2023 – Jun 2026) | $170 | $157 |
| 5 years (Jul 2021 – Jun 2026) | $181 | $161 |
| Since data start (Jul 2019 – Jun 2026) | $268 | $229 |
MUSBX Trailing Returns
Total returns to Jun 2026, from SEC N-PORT.
| Period | Total return |
|---|---|
| YTD | +9.92% |
| 1 year | +19.58% |
| 3 years (annualised) | +19.36% |
| 5 years (annualised) | +12.64% |
MUSBX Annual Returns
Calendar-year total returns of MFS Blended Research Core Equity Fund, compounded from monthly SEC N-PORT returns. Partial years show the months covered.
| Year | Total return |
|---|---|
| 2026 (Jan–Jun) | +9.92% |
| 2025 | +14.91% |
| 2024 | +23.98% |
| 2023 | +27.00% |
| 2022 | −16.88% |
| 2021 | +28.08% |
| 2020 | +14.21% |
| 2019 (Jul–Dec) | +10.89% |
MUSBX 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 | +1.9% | −0.5% | −4.8% | +9.5% | +3.8% | +0.1% | — | — | — | — | — | — |
| 2025 | +3.1% | −1.7% | −5.9% | −1.3% | +6.6% | +5.3% | +1.9% | +2.2% | +3.1% | +1.4% | −0.5% | +0.4% |
| 2024 | +2.5% | +5.6% | +4.3% | −4.5% | +5.5% | +3.2% | +1.1% | +1.1% | +1.3% | +0.1% | +5.4% | −3.1% |
| 2023 | +6.3% | −2.5% | +2.5% | +1.3% | +1.0% | +7.5% | +3.2% | −1.3% | −4.4% | −2.2% | +9.0% | +4.7% |
| 2022 | −4.9% | −3.0% | +3.3% | −7.7% | +1.2% | −8.2% | +8.0% | −3.1% | −8.9% | +8.9% | +4.5% | −6.4% |
| 2021 | −0.4% | +3.1% | +5.5% | +5.2% | +0.4% | +2.0% | +2.0% | +3.1% | −5.2% | +6.5% | −1.3% | +4.7% |
| 2020 | +0.3% | −8.6% | −12.9% | +12.7% | +4.3% | +1.6% | +5.0% | +7.3% | −4.6% | −3.4% | +11.1% | +3.9% |
| 2019 | — | — | — | — | — | — | +1.8% | −2.6% | +2.3% | +2.5% | +3.7% | +2.9% |
MUSBX Risk
Risk measures from monthly returns over Jul 2023 – Jun 2026.
- 3-year volatility (annualised): 12.89%
- 3-year Sharpe ratio: 1.15 (vs 4.5% risk-free rate)
- Best month: +9.54% (Apr 2026)
- Worst month: −5.88% (Mar 2025)
MUSBX Fund Flows
Monthly money in and out of MFS Blended Research Core Equity Fund, from SEC Form N-PORT.
- 12-month net flow: −$320.1M
- 12-month gross sales (incl. reinvestments): $450.9M
- Sales ÷ redemptions: 0.58×
| Month | Sales | Redemptions | Net flow |
|---|---|---|---|
| Jun 2026 | $13.3M | $66.7M | −$53.4M |
| May 2026 | $22.1M | $369.8M | −$347.7M |
| Apr 2026 | $36.6M | $39.6M | −$2.9M |
| Mar 2026 | $30.5M | $33.1M | −$2.6M |
| Feb 2026 | $38.9M | $25.3M | $13.6M |
| Jan 2026 | $19.3M | $40.3M | −$20.9M |
| Dec 2025 | $129.9M | $41.4M | $88.5M |
| Nov 2025 | $16.3M | $31.3M | −$15.0M |
| Oct 2025 | $24.6M | $39.7M | −$15.1M |
| Sep 2025 | $21.4M | $27.1M | −$5.7M |
| Aug 2025 | $79.3M | $25.0M | $54.3M |
| Jul 2025 | $18.8M | $31.9M | −$13.1M |
MUSBX Assets Under Management
Net assets of MFS Blended Research Core Equity Fund by report date, from SEC N-PORT filings.
| Report date | Net assets |
|---|---|
| 2026-06-30 | $1.41B |
| 2026-03-31 | $1.60B |
| 2025-12-31 | $1.66B |
| 2025-09-30 | $1.69B |
| 2025-06-30 | $1.54B |
| 2025-03-31 | $1.41B |
| 2024-12-31 | $1.47B |
| 2024-09-30 | $1.43B |
| 2024-06-30 | $1.35B |
| 2024-03-31 | $1.29B |
| 2023-12-31 | $1.16B |
| 2023-09-30 | $1.07B |
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.