The final S&P PMI manufacturing report comes in at 50.2, unchanged from 50.2 in the March final, and down from 50.7 in the April flash. The Econoday consensus looked for no change from the flash.

The report suggests manufacturing business continues to"flatline in April amid worrying downside risks to the outlook and sharply rising costs," S&P said. Domestic orders supported demand as tariffs depressed export orders and added to uncertainty about the outlook.

The report finds"confidence in the outlook fell to its lowest since last June, while job losses were recorded for the first time in six months. On the price front, tariffs reportedly led to steep increases in both input costs and selling prices. Output charges notably rose to the greatest degree in over two years."

The fact that the index remained barely above the 50 threshold for contraction versus growth is somewhat reassuring. On the other hand, tariff effects noted in the report bode poorly for the future and add to the risk of a downside miss on the ISM manufacturing index for April coming out at 10 am ET.

No change from the flash at 50.7 is expected as manufacturing business stays flat.

Based on monthly questionnaire surveys of selected companies, the Purchasing Managers' Manufacturing Index (PMI) offers an advance indication on month-to-month activity in the private sector economy by tracking changes in variables such as production, new orders, stock levels, employment and prices across manufacturing industries. The final index for the current month is released roughly a week after the flash.

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 ISM manufacturing index in the U.S. and the Markit PMIs in the U.S. and elsewhere, 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.

Markit originally began collecting monthly Purchasing Managers' Index (PMI) data in the U.S. in April 2004, initially from a panel of manufacturers in the U.S. electronics goods producing sector. In May 2007, Markit's U.S. PMI research was extended out to cover producers of metal goods. In October 2009, Markit's U.S. Manufacturing PMI survey panel was extended further to cover all areas of U.S. manufacturing activity. Back data for Markit's U.S. Manufacturing PMI between May 2007 and September 2009 are an aggregation of data collected from producers of electronic goods and metal goods producers, while data from October 2009 are based on data collected from a panel representing the entire U.S. manufacturing economy. Markit's total U.S. Manufacturing PMI survey panel comprises over 600 companies.