Complex sentence: FSA posted for the first quarter of 2008 a $421.6 million net loss due to impairment losses recorded on credit default swaps and losses on its portfolio of US mortgage bonds.
Split into simpler sentences: FSA posted for the first quarter of 2008 a $421.6 million net loss. This was due to impairment losses recorded on credit default swaps and losses on its portfolio of US mortgage bonds.