Nobody knows that for sure.
zero
since the world started
there has been only 22 olimpics in the world
They've always been there since they practically started it.
From September 2nd, 1945 and up to March 9th, 2009: 23,053 days have passed since World War II ended.
it started on April 29th
17
Update! It's now 2021, and it has been 125 years since 1896.
It started March 20th, 2003. As of this March 20th, it will have been seven years.
On September 3rd in 2013, it has been 74 years since World War II started.
Although these two phrases are similar, they key difference is the use of "been". The "has started" statement suggests that the action or event has just recently happened whereas "has been started" creates a time lapse that a significant amount of time as passed.
It's been awhile since the Cubs have BEEN to a World Series -- 1945. It's been even longer since they have WON a World Series -- 1908.