It's been nearly one month since Speaker Nancy Pelosi announced a formal impeachment inquiry on Sept. 24.

Why it matters: It's remarkable how fast it has gotten off the ground. You can see how quickly the Ukraine phone call came out of nowhere to become the all-consuming impeachment topic — way faster than the impeachment inquiries into Richard Nixon and Bill Clinton.

By the numbers:

It was more than a year and a half between the Watergate break-in (June 17, 1972) and the House vote to authorize the impeachment inquiry into Nixon (Feb. 6, 1974).

Nixon resigned about six months later, in the face of certain impeachment and near-certain conviction and removal by the Senate.

It took nearly nine months between the first Washington Post report of an affair between Bill Clinton and Monica Lewinsky (Jan. 21, 1998) and the House vote that authorized his impeachment inquiry (Oct. 8, 1998.)

The inquiry ran 73 days (10 weeks) until Clinton was impeached on Dec. 19, 1998 — just over two months.

He was acquitted by the Senate about two months after that — on Feb. 12, 1999, following a trial that ran for five weeks (37 days).

Now look at the Trump timeline:

It was less than a month and a half ago — Sept. 13 — when House Intelligence Committee Chairman Adam Schiff announced he had issued a subpoena to acting Director of National Intelligence Joseph Maguire for a whistleblower complaint that the Intelligence Community Inspector General "determined to be credible and a matter of ‘urgent concern."

Pelosi announced the impeachment inquiry just 11 days later.

Go deeper ... Trump-Ukraine scandal: The key players, dates and documents