As one of the world's top companies, Apple's quarterly earnings performance is strong, with its market value exceeds US$ 800 billion, holding $ 52.6 billion US Treasury bonds, and is the 23rd largest creditor of the United States. However, Apple performs poorly in three areas: the Chinese market, iPhones revenue contribution and operating profit margins. Tim Cook said the performance of the Chinese market made him feel "very encouraged", though the truth is that the Chinese market turnover has been the in the decline for six quarters consecutively, and as of the end of June quarter it fell 10%.