Investors appeared anxious to hear how sales of Apple’s (NSDQ: AAPL) iPhone have been doing amid the current wider economic turmoil, as the company’s stock was down more than 5 percent by early Monday afternoon, Reuters, reported. Apple will be hosting an event called “Let’s Rock” on Tuesday, during which it is expected to offer details about 3G iPhone sales and the latest version of the iPod Nano. One analyst said that Apple’s stock typically takes a slight dive in advance of big press conference. But economic uncertainty is also playing a role and confidence in Apple appears to be ebbing in some quarters. In an analyst note, Shaw Wu of American Technology Research said: “While there is always room for surprise, it seems this event may be somewhat underwhelming vs previous expectations and events.” And Shannon Cross, an analyst at Cross Research, told Reuters that Apple’s stock is being buffeted by worries about consumer spending and doubts about how quickly they will be refreshing products. Cross added, “It is kind of a buy on the rumor sell on the news kind of stock. Apple often sells off ahead of their announcements.” Matt Kapco, MocoNews.net’s senior entertainment reporter, will be reporting live from the Let’s Rock event tomorrow.