The S&P Global South Korea manufacturing PMI's headline index rose from 48.9 in August to 49.9 in September, indicating that activity in the sector has now almost stabilised after contracting for more than a year. Current conditions, however, remain very weak and respondents report an ongoing lack of confidence that they will improve in the year ahead.

Survey respondents reported output and new orders fell at a less pronounced pace in September but also reported a bigger fall in new export orders. Payrolls were reported to have risen in September, but the survey's measure of business confidence fell to a three-month low. Respondents reported input costs rose at a faster pace in September and that they increased selling prices for the first time in five months.

The Purchasing Managers' Manufacturing Index (PMI) is based on monthly questionnaire surveys of selected companies which provide an advance indication of what is really happening in the private sector economy by tracking changes in variables such as output, new orders, stock levels, employment and prices across the manufacturing sectors.

Investors need to keep their fingers on the pulse of the economy because it dictates how various types of investments will perform. By tracking economic data such as the purchasing managers' manufacturing indexes, investors will know what the economic backdrop is for the various markets. The stock market likes to see healthy economic growth because that translates to higher corporate profits. The bond market prefers less rapid growth and is extremely sensitive to whether the economy is growing too quickly and causing potential inflationary pressures.

The Markit PMI manufacturing data give a detailed look at the manufacturing sector, how busy it is and where things are headed. Since the manufacturing sector is a major source of cyclical variability in the economy, this report has a big influence on the markets. And its sub-indexes provide a picture of orders, output, employment and prices.