As expected, the average selling price (ASP) of Apple's iPad line fell sharply in the fourth quarter of 2012 as the lower-priced iPad Mini reached customers.

The iPad ASP for the quarter was $467, down $101 from the same period the year before, an 18% decline. The fourth-quarter ASP was also 8% lower than the $508 of the preceding quarter, which ended Sept. 30.

Apple started selling the 7.9-in. iPad Mini Nov. 2, well into the fourth quarter, dealing three million the opening weekend. The company sells the device in several configurations, with prices starting at $349.

The company did not break out sales of iPad Minis from iPads, lumping all tablet sales into one figure of 22.9 million, a 48% unit increase over the same quarter of 2011 that outpaced a 22% boost in revenue. The 22.9 million was roughly in line with Wall Street's expectations, although some bulls had had a larger figure in mind.

But Apple wasn't saying how many iPad Mini tablets were among the 22.9 million. Rather, Apple CEO Tim Cook and CFO Peter Oppenheimer said repeatedly that they had not had enough to meet demand.

"We were constrained every week...and we wish that we could have made more," said Cook of the iPad Mini supply.

"There are just too many moving parts," said Ezra Gottheil, analyst with Technology Business Research, when asked whether the ASP decline could provide clues as to how many iPad Mini tablets Apple sold. "You have the iPad Mini, the iPad 2, the [fourth-generation] iPad, and all the LTE and memory options. But a 50-50 split would fit those [sales] numbers."

Apple also told Wall Street analysts yesterday to expect the same kind of year-over-year decline in ASP for the current quarter, which ends March 31.

As of Thursday, Apple's U.S. online store reported a one-week delay between ordering a new iPad Mini and the start of its shipping journey. That delay has been stable since early December 2012.