Note 5: Trading Assets

As of June 30, 2012 and December 31, 2011, trading assets were comprised of marketable debt instruments. Net losses related to trading assets still held at the reporting date were $37 million in the second quarter of 2012 and $28 million in the first half of 2012 (net gains of $16 million in the second quarter of 2011 and $66 million in the first half of 2011). Net gains on the related derivatives were $43 million in the second quarter of 2012 and $43 million in the first half of 2012 (net losses of $13 million in the second quarter of 2011 and $53 million in the first half of 2011).