Despite the attention the Greeks have received concerning the development of mathematics, the Chinese were by no means uninterested in it. About the year 200 B.C.E., the Chinese developed place value notation, and 100 years later, they began to use negative numbers. By the turn of the millennium and a few centuries beyond, they were using decimal fractions (even for the value of “pi” [π]) and the first magic squares (for more information about math puzzles, see “Recreational Math”). By the time European cultures began to decline—from about 530 to 1000 C.E.—the Chinese were contributing not only to the field of mathematics, but also to the study of magnetism, mechanical clocks, physical laws, and astronomy.