What are the largest unions in the US?

As of 2003 these were all of the unions in the US with over 100,000 members in order from the largest; NEA - National Education Association - 2,679,396 SEIU - Service Employees International Union - 1,464,007 UFCW - United Food & Commercial Workers - 1,380,507 IBT - International Brotherhood of Teamsters 1,350,000 AFSCME - American Federation of State, County & Municipal Employees - 1,350,000 LIUNA - Laborers' International Union of North America 840,180 AFT - American Federation of Teachers 770,090 IBEW - International Brotherhood of Electrical Workers 700,548 IAM - International Association of Machinists and Aerospace Workers 673,095 UAW - United Automobile, Aerospace and Agricultural Implement Workers of America 638,722 CWA - Communications Workers of America 557,136 USWA - United Steelworkers of America 532,234 UBC - United Brotherhood of Carpenters and Joiners of America 531,839 IUOE - International Union of Operating Engineers 390,388 NPMHU - National Postal Mailhandlers Union 388,480 UA - United Association of the Journeymen and Apprentices of the Plumbing and Pipe Fitting Industry of the United States and Canada 325,914 NALC - National Association of Letter Carriers 294,315 APWU - American Postal Workers Union 292,901 PACE - Papter, Allied-Industrial, Chemical and Engineering Workers International Union 274,464 IAFF - International Association of Fire Fighers 261,551 HERE - Hotel Employees and Restaurant Employees International Union 249,151 UNITE - Union of Needletrades, Industrial and Textile Employees 209,876 AFGE - American Federation of Government Employees 200,600 AGVA - American Guild of Variety Artists 182,597 UAN - United American Nurses 152,000 OPEIU - Office and Professional Employees International Union 150,882 SMW - Sheet Metal Workers International Association 148,378 BSORIW - International Association of Bridge, Structural, Ornamental and Reinforcing Iron Workers 130,928 IUPAT - International Union of Painters and Allied Trades 115,511 BCTGM - Bakery, Confectionery, Tobacco Workers and Grain Millers International Union 114,618 TWU - Transportation Workers Union of America 110,000 AACSE - American Association of Classified School Employees 109,188 IATSE - International Alliance of Theatrical Stage Employees, Moving Picture Technicians, Artists and Allied Crafts of the United States and Canada 104,102 AFM - American Federation of Musicians of the United States and Canada 102,000 NRLCA - National Rural Letter Carriers' Association 101,810 BAC - International Union of Bricklayers and Allied Craftworkers 101,499 TCU - Transportation Communications International Union 101,228 UMWA - United Mineworkers of America 100,570