Apple sales were up 113 percent in April, according to analysts at Ticonderoga Securities.

Apple Insider reports that the findings of Ticonderoga's 'Apple Barometer' showed strong growth year-on-year for April, though fell short of previous months' increases.

According to the Apple Barometer, Apple sales in March 2011 were up 141 percent on March 2010, February's sales were up 172 percent on the previous year, and January 2011's figures were up 150 percent on January 2010.

"Therefore, despite a weaker than normal April this year, the Apple Barometer can nearly deliver average sequential sales growth performance in (the second quarter of 2011) versus historical metrics," Ticonderoga analyst Brian White wrote in a note to investors.

The figures are calculated by analysing data from Apple's supply chain. This includes the companies that make LCD panels, touchscreens and circuit boards for Apple products.

However, there are a number of considerations that need to be taken into account with Ticonderoga's barometer. For one, there can be a lag between the time that suppliers ship components to Apple and when end users actually purchase the finished products.

Ticonderoga argues, though, that the Apple Barometer gives a good indication of sales trends and is more accurate than simply analysing figures from individual component suppliers such as Foxconn, which only supplies around a quarter of the parts it makes to Apple.