Dow 10,000 may sound impressive, but look back just two years, and the index of the 30 biggest US shares was sitting comfortably above 14,000.
Only a big fall from grace would allow the index to once again breach a level that it had already soared through many years ago. In fact, the first time the Dow hit 10,000 (March 1999) Hugo Chavez first became President of Venezuela, energy powerhouse ExxonMobil was formed, and a bright-eyed and bushy-tailed Britney Spears was unleashed upon the world.
But its not just US stocks going back in time. In the UK, traders were cheerleading the FTSE 100 index through the 5,000 point earlier this month. But just last year, the prospect of the Footsie languishing at such a level was more of a nightmare scenario than something to celebrate.
Back then, the index was at 6,500, thanks to a boom-time rally. Go back further, to 1999, and the index was pushing 7,000 and celebrating an all-time high. So how long do these round-number breaches last, and will they ever be sustainable?