Possible Clues:

• Blair's stint said to have progressively deteriorated
• Dollar : dime :: century : --
• The rotter in the river for years
• 2010s, e.g
• Tony Blair's period as British P.M., e.g
• Group of ten things
• Period of time
• Period that's rotten in terms of radio, according to some
• Rotter in river for long time
• '20s or '30s