The short answer is that the tech giant’s shares are usually down immediately after any major launch - but in the longer term, the only way is up for Apple shares.
In the short term, half of the company’s launches have caused share prices to dip below the post-launch open price and then fail to go back above it for the next 20 days.
In the longer term, however, stocks have rebounded after all but two of the company’s launches.
Tim Cook will be unveiling a new iPhone model later today, alongside a whole host of other goodies, rumoured to include news on the Apple Watch, iOS 9, and Apple TV.
But there are signs investors are growing concerned, as Apple’s stocks are down pre-launch for the first time since the first iPhone was presented back in 2007.
The company’s shares have tumbled 17 per cent since July.