The iPhone’s meteoric rise in the United States isn’t so easy for Apple (AAPL) to duplicate abroad, according to a new report. In a recent note to clients picked up on Monday by AllThingsD, Raymond James analyst Tavis McCourt noted that international iPhone sell-through growth has declined rapidly. Apple’s iPhone sell-through growth rate in non-U.S. markets peaked at more than 110% in the first quarter last year but by the fourth quarter, when Apple sold an estimated 29.2 million iPhones outside of the U.S., growth fell to 35% according to the analyst’s data. “This would be a strong result except for the fact that the comp was easy internationally for Apple as the iPhone 5 launches occurred far earlier this year in most countries than last year’s 4S launch,” McCourt wrote. “March will be a tougher comp internationally.” A graph outlining the analyst’s data follows below.