Why are investors feeling gloomy about Apple's latest quarter?

The software giant will publish results later tonight...

Just two quarters after Apple published the strongest set of quarterly results in corporate history, Apple shares have fallen by over 20% from early 2016 highs.

After riding the iPhone 6 wave which saw the company make massive gains and reassert itself as the benchmark smartphone manufacturer, iPhone orders have stalled as users wait for the details of the iPhone 7 to be revealed.

The number of iPhones – by far Apple’s greatest revenue earner fell for the first time year-on-year since it was launched in 2007 during the first quarter of this year. The phone accounts for two thirds of its sales, and a larger percentage of its profit.

Analysts at Morgan Stanley have predicted that this quarter will represent "the trough" of the current slowdown - but growth from the firm is expected to cool during the next 12 months following its blockbuster 2015.

Investors are expecting some 40m iPhones to have been sold during the three months, this would be a 16% drop year-on-year.



Since Apple introduced the iPhone SE - its cheapest-ever iPhone which brings the company into the mid-level smartphone battleground - investors will be watching the average price of the iPhone's sold by the company to determine whether the more economical offering is drawing demand away from more expensive handsets.

CEO Tim Cook has also indicated that the company could see a lull in sales - even if the iPhone 7 is introduced in September. Given the high levels of purchases and upgrades during the iPhone 6 life cycle, customers may wait until well into 2017 before moving on from Apple's current flagship range.

Apple's slowdown has been compounded by iPad sales taking a 19% fall during the last quarter and Mac computer sales dropping by 9%.

The company is yet to publish official Apple Watch stats as the device has struggled be become a tech-essential.

Apple's total revenue for the quarter is expected to be $42.2bn - this would be a 15% drop on last year - while Fortune expects earnings per share of $1.40 - that's a drop of 24% on 12 months ago.

Here's a full lowdown on what we know (and think we know) about the next iPhone launch.