Return Attribution — MFS Investment Management
← Portfolio Analysis
Clone backtest (value-weighted, one-quarter signal lag): each position's contribution = its portfolio weight × next-quarter return. Contribution sums equal the segment return of the clone.
MFS Investment Management (13F portfolio cloned at quarter-end weights) delivered a +1.54% return over the 2026-Q2 → latest period. The clone return is the sum of each position's contribution — portfolio weight times next-quarter price return.
Top drivers in 2026-Q2 → latest: MSFT (+1.09%), NVDA (+0.68%), AAPL (+0.51%). Biggest drags: KLAC (-0.51%), STX (-0.16%), CAT (-0.15%). Across all 20 segmented periods, 28 stocks made a positive cumulative contribution and 35 subtracted from performance.
This attribution is a diagnostic tool, not a trading signal. The clone uses end-of-quarter holdings (45+ days after filing, so stale by design), applies quarter-end prices only, and ignores intra-quarter trades, shorts, and derivatives that 13F cannot show.
2026-Q2 → latest segment return
+1.54%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
2.8% |
+39.1% |
+1.09% |
| NVDA |
4.4% |
+15.5% |
+0.68% |
| AAPL |
2.8% |
+17.8% |
+0.51% |
| TMO |
0.7% |
+30.0% |
+0.22% |
| META |
0.7% |
+28.2% |
+0.19% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| KLAC |
1.4% |
-35.5% |
-0.51% |
| STX |
0.8% |
-19.5% |
-0.16% |
| CAT |
0.6% |
-25.1% |
-0.15% |
| AON |
0.8% |
-16.5% |
-0.14% |
| HONA |
0.4% |
-30.3% |
-0.13% |
2026-Q1 → 2026-Q2 segment return
+8.07%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| GOOGL |
2.4% |
+24.3% |
+0.57% |
| NVDA |
3.9% |
+14.0% |
+0.55% |
| STX |
0.3% |
+145.7% |
+0.5% |
| TSM |
1.2% |
+39.6% |
+0.46% |
| AAPL |
2.7% |
+13.4% |
+0.36% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| KLAC |
0.8% |
-79.4% |
-0.66% |
| ACN |
0.9% |
-36.7% |
-0.31% |
| AEM |
0.8% |
-23.6% |
-0.2% |
| XOM |
1.0% |
-18.7% |
-0.19% |
| COP |
0.9% |
-20.7% |
-0.19% |
2025-Q4 → 2026-Q1 segment return
-2.68%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| TTE |
0.9% |
+39.9% |
+0.34% |
| XOM |
0.8% |
+39.7% |
+0.3% |
| COP |
0.7% |
+42.1% |
+0.29% |
| JNJ |
1.1% |
+18.2% |
+0.2% |
| FNV |
0.8% |
+19.7% |
+0.16% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
4.3% |
-22.8% |
-0.97% |
| NVDA |
4.1% |
-6.2% |
-0.25% |
| ACN |
0.9% |
-26.1% |
-0.24% |
| KKR |
0.8% |
-27.3% |
-0.21% |
| GOOGL |
2.6% |
-8.1% |
-0.21% |
2025-Q3 → 2025-Q4 segment return
+0.85%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| GOOGL |
1.8% |
+28.8% |
+0.52% |
| AAPL |
2.3% |
+7.3% |
+0.17% |
| TSM |
1.4% |
+9.6% |
+0.13% |
| UBS |
1.0% |
+13.0% |
+0.13% |
| JNJ |
1.0% |
+11.4% |
+0.12% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
4.9% |
-6.1% |
-0.3% |
| META |
1.8% |
-10.2% |
-0.18% |
| ETN |
0.9% |
-14.7% |
-0.13% |
| SPOT |
0.6% |
-16.8% |
-0.11% |
| NFLX |
0.5% |
-21.5% |
-0.1% |
2025-Q2 → 2025-Q3 segment return
+4.94%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| GOOGL |
1.5% |
+37.9% |
+0.56% |
| NVDA |
2.9% |
+17.9% |
+0.52% |
| AAPL |
1.7% |
+23.4% |
+0.39% |
| TSM |
1.1% |
+22.9% |
+0.25% |
| FNV |
0.6% |
+35.2% |
+0.22% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| CI |
1.2% |
-12.4% |
-0.15% |
| ACN |
0.9% |
-17.1% |
-0.15% |
| KVUE |
0.6% |
-22.5% |
-0.14% |
| FISV |
0.4% |
-25.2% |
-0.09% |
| PGR |
1.1% |
-7.5% |
-0.08% |
2025-Q1 → 2025-Q2 segment return
+8.91%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
3.9% |
+33.0% |
+1.29% |
| NVDA |
2.1% |
+46.5% |
+0.99% |
| META |
1.8% |
+28.8% |
+0.52% |
| TSM |
0.9% |
+37.2% |
+0.33% |
| AMZN |
2.0% |
+16.0% |
+0.31% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| AON |
1.3% |
-10.6% |
-0.14% |
| AAPL |
1.9% |
-7.1% |
-0.14% |
| FISV |
0.6% |
-21.9% |
-0.13% |
| BDX |
0.5% |
-24.3% |
-0.13% |
| COP |
0.9% |
-13.8% |
-0.12% |
2024-Q4 → 2025-Q1 segment return
-2.03%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| CI |
1.0% |
+19.7% |
+0.2% |
| PGR |
1.0% |
+18.1% |
+0.19% |
| AON |
1.3% |
+11.8% |
+0.16% |
| MCK |
0.9% |
+18.1% |
+0.16% |
| FNV |
0.5% |
+34.4% |
+0.15% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| NVDA |
2.8% |
-19.9% |
-0.56% |
| MSFT |
4.4% |
-11.3% |
-0.5% |
| GOOGL |
2.3% |
-18.3% |
-0.41% |
| AMZN |
2.2% |
-13.9% |
-0.3% |
| TSLA |
0.8% |
-36.3% |
-0.27% |
2024-Q3 → 2024-Q4 segment return
+0.49%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| AMZN |
1.8% |
+18.3% |
+0.33% |
| NVDA |
2.5% |
+10.7% |
+0.26% |
| JPM |
1.6% |
+13.8% |
+0.22% |
| V |
1.3% |
+14.9% |
+0.19% |
| AAPL |
2.0% |
+7.4% |
+0.15% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| CI |
1.2% |
-20.0% |
-0.23% |
| LIN |
1.2% |
-12.0% |
-0.15% |
| KLAC |
0.6% |
-18.6% |
-0.11% |
| ELV |
0.4% |
-28.8% |
-0.11% |
| TMO |
0.6% |
-15.9% |
-0.1% |
2024-Q2 → 2024-Q3 segment return
+4.43%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| GOOGL |
2.7% |
+34.0% |
+0.91% |
| AON |
1.2% |
+17.9% |
+0.21% |
| META |
1.5% |
+13.3% |
+0.19% |
| AAPL |
1.9% |
+10.2% |
+0.19% |
| ACN |
1.0% |
+17.0% |
+0.18% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
5.2% |
-4.1% |
-0.22% |
| CDNS |
0.9% |
-11.9% |
-0.11% |
| AMZN |
1.9% |
-3.9% |
-0.08% |
| NXPI |
0.7% |
-10.8% |
-0.07% |
| SCHW |
0.6% |
-11.7% |
-0.07% |
2024-Q1 → 2024-Q2 segment return
+1.23%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| NVDA |
2.5% |
+37.3% |
+0.93% |
| AAPL |
1.5% |
+23.6% |
+0.36% |
| TSM |
1.2% |
+27.8% |
+0.33% |
| MSFT |
4.9% |
+6.5% |
+0.32% |
| ADI |
0.9% |
+16.8% |
+0.15% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| AON |
1.2% |
-11.1% |
-0.14% |
| ACN |
1.1% |
-12.1% |
-0.14% |
| CMCSA |
1.1% |
-9.7% |
-0.11% |
| CI |
1.2% |
-8.6% |
-0.11% |
| COP |
1.1% |
-9.6% |
-0.1% |
2023-Q4 → 2024-Q1 segment return
+8.06%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| NVDA |
1.5% |
+82.7% |
+1.24% |
| MSFT |
4.6% |
+11.8% |
+0.54% |
| META |
1.1% |
+37.6% |
+0.4% |
| ETN |
1.1% |
+30.2% |
+0.32% |
| TSM |
1.0% |
+31.2% |
+0.3% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| AAPL |
1.8% |
-10.9% |
-0.2% |
| CHTR |
0.3% |
-25.2% |
-0.08% |
| HON |
1.0% |
-6.7% |
-0.07% |
| XEL |
0.4% |
-13.2% |
-0.05% |
| ADBE |
0.3% |
-15.4% |
-0.04% |
2023-Q3 → 2023-Q4 segment return
+8.49%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
4.3% |
+18.9% |
+0.82% |
| AMZN |
1.4% |
+19.5% |
+0.28% |
| JPM |
1.6% |
+17.3% |
+0.27% |
| UBS |
1.0% |
+25.4% |
+0.24% |
| AAPL |
1.8% |
+12.2% |
+0.22% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| AON |
1.6% |
-10.2% |
-0.16% |
| FNV |
0.5% |
-16.5% |
-0.08% |
| CHTR |
0.5% |
-11.6% |
-0.06% |
| COP |
1.2% |
-2.6% |
-0.03% |
| BDX |
0.5% |
-5.3% |
-0.03% |
2023-Q2 → 2023-Q3 segment return
-2.38%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| UBS |
0.8% |
+21.6% |
+0.16% |
| COP |
1.0% |
+16.7% |
+0.16% |
| CMCSA |
1.4% |
+6.7% |
+0.09% |
| CHTR |
0.4% |
+19.7% |
+0.09% |
| ETN |
1.0% |
+6.5% |
+0.06% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
4.5% |
-7.3% |
-0.32% |
| AAPL |
2.0% |
-11.9% |
-0.24% |
| JCI |
0.7% |
-21.4% |
-0.15% |
| HON |
1.1% |
-11.0% |
-0.12% |
| TSM |
0.9% |
-14.2% |
-0.12% |
2023-Q1 → 2023-Q2 segment return
+5.56%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
4.0% |
+18.0% |
+0.72% |
| NVDA |
0.7% |
+52.1% |
+0.37% |
| AMZN |
1.3% |
+25.9% |
+0.33% |
| AAPL |
1.8% |
+17.8% |
+0.32% |
| JPM |
1.4% |
+11.9% |
+0.17% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| TMO |
1.6% |
-9.4% |
-0.15% |
| MSCI |
0.6% |
-16.2% |
-0.1% |
| A |
0.4% |
-12.8% |
-0.05% |
| WAT |
0.3% |
-13.9% |
-0.04% |
| IFF |
0.3% |
-12.5% |
-0.04% |
2022-Q4 → 2023-Q1 segment return
+2.94%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
3.5% |
+20.1% |
+0.7% |
| AAPL |
1.5% |
+26.9% |
+0.39% |
| NVDA |
0.3% |
+89.9% |
+0.3% |
| AMZN |
1.1% |
+23.0% |
+0.26% |
| CDNS |
0.6% |
+30.8% |
+0.19% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| SCHW |
0.8% |
-36.9% |
-0.31% |
| CI |
1.3% |
-22.5% |
-0.3% |
| HON |
1.4% |
-15.0% |
-0.21% |
| JNJ |
1.3% |
-12.3% |
-0.17% |
| COP |
1.0% |
-15.0% |
-0.15% |
2022-Q3 → 2022-Q4 segment return
+10.21%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| JPM |
1.3% |
+28.3% |
+0.38% |
| HON |
1.2% |
+28.3% |
+0.35% |
| V |
1.6% |
+16.9% |
+0.27% |
| MRK |
0.9% |
+29.7% |
+0.27% |
| CI |
1.2% |
+19.8% |
+0.25% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| AMZN |
1.6% |
-25.7% |
-0.42% |
| AAPL |
1.7% |
-5.5% |
-0.09% |
| D |
0.6% |
-11.3% |
-0.06% |
| MRVI |
0.1% |
-43.9% |
-0.06% |
| FIS |
0.4% |
-10.2% |
-0.04% |
2022-Q2 → 2022-Q3 segment return
-5.33%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| COP |
0.7% |
+16.1% |
+0.12% |
| SCHW |
0.8% |
+14.1% |
+0.11% |
| CDNS |
1.0% |
+8.9% |
+0.09% |
| AMZN |
1.4% |
+5.9% |
+0.08% |
| NDAQ |
0.7% |
+11.5% |
+0.08% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| CMCSA |
1.4% |
-25.3% |
-0.36% |
| MSFT |
3.7% |
-9.3% |
-0.34% |
| CHTR |
0.9% |
-35.3% |
-0.31% |
| ADBE |
0.8% |
-24.8% |
-0.21% |
| V |
1.7% |
-9.5% |
-0.16% |
2021-Q4 → 2022-Q1 segment return
-4.44%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| COP |
0.4% |
+39.7% |
+0.17% |
| AON |
1.5% |
+8.3% |
+0.13% |
| MDT |
1.3% |
+7.9% |
+0.11% |
| CB |
0.8% |
+10.7% |
+0.09% |
| CNI |
0.9% |
+9.0% |
+0.08% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| ACN |
2.1% |
-18.4% |
-0.38% |
| MSFT |
3.8% |
-7.9% |
-0.3% |
| SHW |
0.8% |
-29.0% |
-0.24% |
| META |
0.7% |
-33.8% |
-0.24% |
| TMO |
2.1% |
-10.1% |
-0.21% |
2021-Q3 → 2021-Q4 segment return
+2.76%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| MSFT |
3.4% |
+19.3% |
+0.65% |
| TMO |
2.0% |
+16.8% |
+0.34% |
| AAPL |
1.3% |
+25.4% |
+0.34% |
| CDNS |
1.0% |
+23.1% |
+0.22% |
| NVDA |
0.5% |
+41.5% |
+0.2% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| PYPL |
0.7% |
-27.7% |
-0.19% |
| CMCSA |
1.9% |
-10.0% |
-0.19% |
| C |
0.6% |
-13.3% |
-0.07% |
| SE |
0.2% |
-30.2% |
-0.05% |
| JPM |
1.7% |
-2.9% |
-0.05% |
2021-Q2 → 2021-Q3 segment return
+0.64%
Top contributors
| Symbol | Weight | Return | Contrib |
|---|
| AON |
1.4% |
+19.7% |
+0.28% |
| TMO |
1.8% |
+13.3% |
+0.24% |
| GOOGL |
2.1% |
+9.6% |
+0.2% |
| MSFT |
3.3% |
+4.1% |
+0.14% |
| CNI |
1.0% |
+9.6% |
+0.1% |
Biggest drags
| Symbol | Weight | Return | Contrib |
|---|
| AMZN |
1.9% |
-4.3% |
-0.08% |
| PYPL |
0.8% |
-10.6% |
-0.08% |
| V |
1.7% |
-4.7% |
-0.08% |
| TSM |
1.2% |
-6.5% |
-0.08% |
| BABA |
0.2% |
-34.7% |
-0.06% |
Cumulative Contribution (all segments)