The Chinese currency has been a global point of contention for nearly a decade. China officially ended the renminbi’s fixed peg to the dollar in 2005. Since then, it has risen in two long, slow climbs. The first was from July 2005 to August 2008, when it was interrupted by the global financial crisis. The renminbi then resumed its rise from June 2010 to early last year, when it dipped slightly, then stabilized.