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Over the course of 2013, the corporation began the sale of its US shale gas assets and cancelled a US$20 billion gas project that was to be constructed in the US state of Louisiana. A new CEO Ben van Beurden was appointed in January 2014, prior to the announcement that the corporation's overall performance in 2013 was 38 per cent lower than 2012—the value of Shell's shares fell by 3 per cent as a result. Following the sale of the majority of its Australian assets in February 2014, the corporation plans to sell a further US$15 billion worth of assets in the period leading up to 2015, with deals announced in Australia, Brazil and Italy.

What was the value of assets the corporation planned to sell leading up to 2015?
US$15 billion