Read this: The governments of Australia and New Zealand responded to the 2011 fresh-water crisis by supplying temporary desalination plants, and assisted in the repair of the existing desalination unit that was donated by Japan in 2006. In response to the 2011 drought, Japan funded the purchase of a 100 m3/d desalination plant and two portable 10 m3/d plants as part of its Pacific Environment Community (PEC) program. Aid programs from the European Union and Australia also provided water tanks as part of the longer term solution for the storage of available fresh water.

In what year had Japan previously donated a desalination plant to Tuvalu?
What is the answer? (If it cannot be answered, return "unanswerable")
2006