| 1 | 488999 | ALL OTHER SUPPORT ACTIVITIES FOR TRANSPORTATION | $750,352,873 | 1 |
| 2 | 541330 | ENGINEERING SERVICES | $619,699,620 | 5 |
| 3 | 541512 | COMPUTER SYSTEMS DESIGN SERVICES | $543,231,047 | 7 |
| 4 | 541519 | OTHER COMPUTER RELATED SERVICES | $332,746,261 | 159 |
| 5 | 236220 | COMMERCIAL AND INSTITUTIONAL BUILDING CONSTRUCTION | $182,488,198 | 2 |
| 6 | 541611 | ADMINISTRATIVE MANAGEMENT AND GENERAL MANAGEMENT CONSULTING SERVICES | $92,944,546 | 3 |
| 7 | 541714 | RESEARCH AND DEVELOPMENT IN BIOTECHNOLOGY (EXCEPT NANOBIOTECHNOLOGY) | $76,510,367 | 2 |
| 8 | 517110 | WIRED TELECOMMUNICATIONS CARRIERS | $68,249,555 | 1 |
| 9 | 518210 | DATA PROCESSING, HOSTING, AND RELATED SERVICES | $60,679,594 | 1 |
| 10 | 332999 | ALL OTHER MISCELLANEOUS FABRICATED METAL PRODUCT MANUFACTURING | $44,462,993 | 1 |
| 11 | 522390 | OTHER ACTIVITIES RELATED TO CREDIT INTERMEDIATION | $41,992,525 | 1 |
| 12 | 541511 | CUSTOM COMPUTER PROGRAMMING SERVICES | $9,609,359 | 5 |
| 13 | 541712 | RESEARCH AND DEVELOPMENT IN THE PHYSICAL, ENGINEERING, AND LIFE SCIENCES (EXCEPT BIOTECHNOLOGY) | $8,692,998 | 2 |
| 14 | 561611 | INVESTIGATION AND PERSONAL BACKGROUND CHECK SERVICES | $7,567,498 | 1 |
| 15 | 611710 | EDUCATIONAL SUPPORT SERVICES | $5,915,482 | 1 |
| 16 | 541990 | ALL OTHER PROFESSIONAL, SCIENTIFIC, AND TECHNICAL SERVICES | $5,095,662 | 4 |
| 17 | 611430 | PROFESSIONAL AND MANAGEMENT DEVELOPMENT TRAINING | $4,982,623 | 1 |
| 18 | 519120 | LIBRARIES AND ARCHIVES | $4,518,583 | 2 |
| 19 | 541715 | RESEARCH AND DEVELOPMENT IN THE PHYSICAL, ENGINEERING, AND LIFE SCIENCES (EXCEPT NANOTECHNOLOGY AND BIOTECHNOLOGY) | $3,544,466 | 3 |
| 20 | 561110 | OFFICE ADMINISTRATIVE SERVICES | $2,661,670 | 1 |
| 21 | 722310 | FOOD SERVICE CONTRACTORS | $2,643,578 | 1 |
| 22 | 561210 | FACILITIES SUPPORT SERVICES | $2,602,000 | 1 |
| 23 | 541613 | MARKETING CONSULTING SERVICES | $1,546,066 | 1 |
| 24 | 337215 | SHOWCASE, PARTITION, SHELVING, AND LOCKER MANUFACTURING | $1,174,088 | 5 |
| 25 | 541930 | TRANSLATION AND INTERPRETATION SERVICES | $1,168,537 | 4 |
| 26 | 519190 | ALL OTHER INFORMATION SERVICES | $1,078,312 | 1 |
| 27 | 561320 | TEMPORARY HELP SERVICES | $924,742 | 2 |
| 28 | 811219 | OTHER ELECTRONIC AND PRECISION EQUIPMENT REPAIR AND MAINTENANCE | $891,642 | 8 |
| 29 | 541820 | PUBLIC RELATIONS AGENCIES | $729,939 | 1 |
| 30 | 624190 | OTHER INDIVIDUAL AND FAMILY SERVICES | $379,694 | 1 |
| 31 | 334111 | ELECTRONIC COMPUTER MANUFACTURING | $374,071 | 2 |
| 32 | 511210 | SOFTWARE PUBLISHERS | $302,593 | 3 |
| 33 | 541612 | HUMAN RESOURCES CONSULTING SERVICES (2007), HUMAN RESOURCES AND EXECUTIVE SEARCH CONSULTING SERVICES (2002) | $295,046 | 1 |
| 34 | 541614 | PROCESS, PHYSICAL DISTRIBUTION, AND LOGISTICS CONSULTING SERVICES | $210,609 | 1 |
| 35 | 339112 | SURGICAL AND MEDICAL INSTRUMENT MANUFACTURING | $175,122 | 1 |
| 36 | 334516 | ANALYTICAL LABORATORY INSTRUMENT MANUFACTURING | $171,329 | 2 |
| 37 | 561920 | CONVENTION AND TRADE SHOW ORGANIZERS | $166,642 | 1 |
| 38 | 811310 | COMMERCIAL AND INDUSTRIAL MACHINERY AND EQUIPMENT (EXCEPT AUTOMOTIVE AND ELECTRONIC) REPAIR AND MAINTENANCE | $107,840 | 1 |
| 39 | 337910 | MATTRESS MANUFACTURING | $83,885 | 1 |
| 40 | 334510 | ELECTROMEDICAL AND ELECTROTHERAPEUTIC APPARATUS MANUFACTURING | $76,000 | 1 |
| 41 | 335929 | OTHER COMMUNICATION AND ENERGY WIRE MANUFACTURING | $74,147 | 1 |
| 42 | 337214 | OFFICE FURNITURE (EXCEPT WOOD) MANUFACTURING | $55,651 | 2 |
| 43 | 541380 | TESTING LABORATORIES AND SERVICES | $9,460 | 1 |
| 44 | 493120 | REFRIGERATED WAREHOUSING AND STORAGE | $7,760 | 1 |
| 45 | 332722 | BOLT, NUT, SCREW, RIVET, AND WASHER MANUFACTURING | $254 | 1 |