Czech manufacturing activity weakened for a third straight month in August as high inflation continued to bite into customer demand, the S&P Global Purchasing Managers' Index (PMI) showed on Thursday.

The headline PMI was unchanged at a more than two-year low of 46.8 in August, and it has been below the 50 mark that divides expansion from contraction since June. Analysts polled by Reuters had forecast a tiny uptick to a reading of 46.9.

The survey showed the fall in new sales was the sharpest in over two years. Output and orders continued to contract, although at a slower pace in the first case.

Data, though, also showed a slowdown in input costs. Month/Year 08/22 07/22 08/21 Purchasing Managers' Index 46.8 46.8 61.0 Output 45.9 43.9 58.1 NOTE. All indices are seasonally adjusted and are based on data collected from purchasing executives in 300 manufacturing companies in the Czech Republic. (Reporting by Jason Hovet; Editing by Hugh Lawson)