Apple’s COO and — many say — CEO-in-waiting Tim Cook has presided over a near-doubling of Apple’s margins over the past decade. Known as a supply chain maven and operations specialist, Cook has stepped up to the plate during CEO Steve Jobs’ three medical absences.

On Wednesday, Cook is expected to face questions about the company’s succession plan during Apple’s annual shareholders’ meeting at 1 Infinte Loop.

Here’s a look at how Apple has fared during Cook’s tenure.

(Apple (L-R) COO Tim Cook, CEO Steve Jobs and Robert Mansfield, senior vice president, Mac Hardware Engineering appear onstage during Q&A period at news conference on antenna problems with the iPhone 4 at Apple headquarters in Cupertino, California, July 16, 2010.)