Task: Question Answering
Input (English): Passage: Diamond industry  Israel is one of the worlds three major centers for Diamond cutting diamonds, alongside Belgium and India. Israels net polished diamond exports slid 22.8 percent in 2012 as polished diamond exports fell to $5.56 billion from $7.2 billion in 2011. Net exports of rough diamonds dropped 20.1 percent to $2.8 billion and net exports of polished diamonds slipped 24.9 percent to $4.3 billion, while net rough diamond imports dropped 12.9 percent to $3.8 billion. Net exports and imports have dropped due to the ongoing Global financial crisis, particularly within the European sovereign-debt crisis and the United States. The United States is the largest market accounting for 36% of overall export market for polished diamonds while Hong Kong remains at second with 28 percent and Belgium at 8 percent coming in third. , cut diamonds were Israels largest export product, comprising 23.2% of all exports. 
Question: How many dollars in billions did Israel's polished diamond exports fall in 2011? 
Answer type: Number 
Output (English): 1.64.