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NEW YORK, Sept 29 (Reuters) - The U.S. dollar's share of global currency reserves fell in the second quarter, but it remains the most-widely held reserve currency by central banks around the world, data from the International Monetary Fund showed on Friday.
The share of U.S. dollar reserves, however, has declined for two straight quarters.
Reserves in U.S. dollars totaled $5.91 trillion, or roughly 63.8 percent of allocated reserves, in the second quarter, down from a 64.6 percent share in the first quarter, when dollar reserves totaled $5.71 trillion.
Global reserves are assets of central banks held in different currencies, primarily used to support their liabilities. Central banks sometimes have used reserves to help support their respective currencies.
The euro's share edged modestly higher to nearly 20 percent in the second quarter, from about 19.3 percent in the first. The single currency's share of reserves was at 28 percent at its peak in 2009.
China's share of allocated currency reserves was 0.1 percent in the second quarter, little changed from the previous quarter. The IMF had reported the yuan's share of central bank holdings for the first time in the fourth quarter of 2016.
The yen's share of currency reserves, meanwhile, was at 4.6 percent in the second quarter, unchanged from the first.
IMF data also showed that global reserves rose to a record $11.12 trillion from $10.90 trillion in the first quarter.
The total amount of allocated currency holdings also grew, to $9.26 trillion, from $8.84 trillion previously.
Allocated reserves now include part of China's official reserves, with full currency allocation disclosure set to take two to three years. With China's disclosure, the share of allocated reserves as a percentage of the total was at 83 percent in the second quarter.
Unallocated reserves, or those that have not been reported to the IMF, continued their decline, sliding to $1.86 trillion in the second quarter from $2.06 trillion in the first quarter.
Unallocated reserves represented just 16.6 percent of total global FX reserves, down from 19 percent in the first quarter. It was widely believed in the currency market that part of China's reserves were in the unallocated pool.
The Australian and Canadian dollars, which over the last year have been included in the reserves composition, showed shares of 1.7 percent and 1.9 percent, respectively.
For the full breakdown of the data, click on; http://data.imf.org/?sk=E6A5F467-C14B-4AA8-9F6D-5A09EC4E62A4 (Reporting by Gertrude Chavez-Dreyfuss; Editing by Bernadette Baum and Dan Grebler)