Global exports of Swiss watches plummeted in March, amid a dramatic contraction of sales in main markets Hong Kong and the United States.

Exports fell 16.1 percent from March 2015 to 1.5 billion Swiss francs ($1.5 billion, 1.4 billion euros), the Federation of the Swiss Watch Industry (FHS) said.

In 2015, watch exports recorded their first full-year decline since 2009, contracting by 3.3 percent with weakening Hong Kong demand already the main factor.

And FHS said the downward trend was accelerating.

The numbers last month, it said, were "the lowest March figures since 2011."

"The scale of the downturn is also unusual, since we must go back to the crisis of 2009 to find rates of variation of this order," it said.

Analysts voiced disappointment at lacking improvements on the market.

"The mood amongst watch retailers seems to have deteriorated in recent months," Citi Research analyst Thomas Chauvet said in a note, blaming "subdued economic conditions, stock market and (currency) volatility, travel fears after several terrorist attacks in Europe and depressed oil prices."

The slump came as top Swiss watch market Hong Kong saw one of its sharpest downturns, slumping a full 37.7 percent compared to March a year earlier.

The Hong Kong watch market has steadily shrunk since the 2014 pro-democracy Umbrella protests chased away the wealthy Chinese tourists who previously travelled there in droves to purchase luxury timepieces.

And the strengthening Hong Kong dollar has since prompted them to look to other markets where prices are more attractive.

Exports to the United States, the second largest market for Swiss watches, meanwhile fell 32.9 percent in March.

And the market in China slumped 13.7 percent, countering signs of a timid recovery seen at the end of last year.

After years of euphoric growth, the Chinese market took a major hit following a 2013 Beijing decision to crack down on corruption by banning extravagant gifts like expensive watches to public officials.

Germany was basically the only market bucking the downward trend last month, showing 2.2 percent growth over March 2015, "which confirms the steady improvement in its situation," FHS said.

Japan, which had recently provided a small dose of optimism to the gloomy market, meanwhile disappointed, recording a 9.4 percent drop in demand from a year earlier.