Historical clue formulations

• ___ 500 — 2020-02-07
• Dow alternative — 2019-12-14
• Wall St. "500" — 2019-05-01
• ___ 500 — 2018-10-10
• Wall Street index, for short — 2017-09-20
• Wall St. "500" — 2016-08-21
• 500 managers, for short? — 2015-04-22
• ___ 500 — 2011-10-12
• Market yardstick, for short — 2009-01-31