Two big questions ahead of Apple earnings today

The two big questions investors and analysts have going into Apple's earnings report later today are also the two things we predicted would be challenges ahead of this year's iPhone release:

1. How many iPhone Xs can Apple supply over the next few months?
2. Just how much will the high-end iPhone dent demand for the iPhone 8, which Apple is able to make in significantly greater quantity?

Other numbers will also be closely watched, including Apple's sales and earnings forecast for the all-important holiday quarter. That said, iPhone 8 demand and iPhone 10 will be key components of the coming quarter's earnings.

By the numbers: Analysts are expecting Apple to report per-share earnings of $1.87 on revenue of $51.2 billion, according to Zacks. For the December quarter, analysts are looking for earnings of $3.77 per share, on revenue of $83.3 billion.