| 2009 | 1 | 0 | $864,190 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $864,190 | - | - |
| 2008 | 3 | 0 | $318,101 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $318,101 | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 0 | - | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | - | - | - |
| 2007 | 3 | 0 | $872,438 | $0 | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 0 | $477,408 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | $395,030 | - | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | - | - | - |
| 2006 | 3 | 3 | $5,243,771 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $4,402,257 | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 3 | $547,335 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | $294,179 | - | - |
| 2005 | 3 | 6 | $9,542,525 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $4,313,800 | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 6 | $2,842,863 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | $2,385,862 | - | - |
| 2004 | 3 | 6 | $1,508,462 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $1,507,161 | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 6 | $1,059 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | $242 | - | - |
| 2003 | 3 | 0 | $480,543,774 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $480,358,768 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | $183,451 | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 0 | $1,555 | - | - |
| 2002 | 3 | 0 | $907,002,769 | $304,165 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $864,565,071 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 0 | $42,428,903 | $304,165 | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 0 | $8,795 | - | - |
| 2001 | 3 | 3 | $874,223,777 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | $772,801,000 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 3 | $99,616,815 | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 0 | $1,805,962 | - | - |
| 2000 | 3 | 2,631 | $0 | $0 | - |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 0 | - | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 770 | - | - | - |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 2,631 | - | - | - |
| 1999 | 3 | 3,373 | $1,284,190,518 | $25,336,000 | $7,511iApproximate average salary by contribution assumption: employee only about $187,785 at 4% or $125,190 at 6%; with 50% employer match about $125,190 at 4% or $83,460 at 6%; with 100% employer match about $93,893 at 4% or $62,595 at 6%. |
| Employee Retirement Plan of Stone and Webster Inc and Participating Subsidiaries | - | 2,481 | $808,782,000 | - | - |
| Employee Investment Plan of Stone and Webster Inc. and Participating Subsidaries | - | 3,373 | $437,730,575 | $20,880,000 | $6,190iApproximate average salary by contribution assumption: employee only about $154,758 at 4% or $103,172 at 6%; with 50% employer match about $103,172 at 4% or $68,782 at 6%; with 100% employer match about $77,379 at 4% or $51,586 at 6%. |
| Employee Stock Ownership Plan of Stone and Webster Incorporated and Participating Subsidiaries | - | 2,870 | $37,677,943 | $4,456,000 | $1,553iApproximate average salary by contribution assumption: employee only about $38,815 at 4% or $25,877 at 6%; with 50% employer match about $25,877 at 4% or $17,251 at 6%; with 100% employer match about $19,408 at 4% or $12,938 at 6%. |