Historical clue formulations

• Letters after Chuck Schumer's name — 2020-02-04
• Letters after Chuck Schumer or Kirsten Gillibrand — 2019-06-13
• Letters after Sen. Kirsten Gillibrand's name — 2015-03-29
• Letters after Sen. Charles Schumer's name — 2012-08-03
• Letters after Daniel Moynihan's name — 1998-10-26
• Letters after Moynihan's name — 1994-09-18