Taking into account the holiday, HSBC Greater China economist Donna Kwok said the average of January's and February's reading just under 51.4 still indicated decent growth, and was stronger than data for the final quarter of 2012.

WSJ: Asian Manufacturing Growth Slows, Data Show

And if one looks at the real exchange rate--essentially taking into account price differences between the U.S. and China--the yuan has actually depreciated against the dollar.

FORBES: China's Currency Problems