Historical clue formulations

• Dial-up unit — 2013-12-01
• Modem speed unit — 2004-03-30
• Modem speed measure — 2003-08-10
• Data transmission rate — 2003-05-04
• Transfer rate — 2000-04-22
• Unit of speed — 1999-10-16
• Data transfer speed unit — 1998-12-12
• Unit of data transmission — 1997-01-12