The S&P Global Hong Kong PMI survey indicates that Hong Kong's economy contracted in May for the fourth consecutive month but at a less pronounced rate, with the headline index increasing to 49.0 from a nine-month low of 48.3 in April. Respondents noted that a pause in tariff increases by the United States had helped to stabilise conditions but continued to express concerns about the impact of global trade tensions.

Survey respondents reported declines in output, new orders, and new export orders in May, with the latter falling at the less pronounced rate as demand from mainland China stabilised. Payrolls were reported to have been increased for the first time in four months but the survey's measure of business confidence remains at very low levels. Respondents reported a smaller increase in input costs and a small increase in selling prices after two months of price reductions.

The Nikkei Hong Kong PMI is based on data compiled from monthly replies to questionnaires sent to purchasing executives in over 300 companies. The panel is stratified by company size and by Standard Industrial Classification (SIC) group, based on industry contribution to Hong Kong GDP. Survey responses reflect the change, if any, in the current month compared to the previous month based on data collected mid-month. For each of the indicators the ‘Report’ shows the percentage reporting each response, the net difference between the number of higher/better responses and lower/worse responses, and the ‘diffusion’ index. This index is the sum of the positive responses plus a half of those responding ‘the same’.

The Purchasing Managers’ Index is a composite index based on five of the individual indexes with the following weights: New Orders - 0.3, Output - 0.25, Employment - 0.2, Suppliers’ Delivery Times - 0.15, Stock of Items Purchased - 0.1, with the Delivery Times index inverted so that it moves in a comparable direction.

Diffusion indexes have the properties of leading indicators and are convenient summary measures showing the prevailing direction of change. An index reading above 50 indicates an overall increase in that variable, below 50 an overall decrease.

The Purchasing Managers Index (PMI) survey has developed an outstanding reputation for providing the most up-to-date possible indication of what is really happening in the private sector economy by tracking variables such as sales, employment, inventories and prices. The indices are widely used by businesses, governments and economic analysts in financial institutions to help better understand business conditions and guide corporate and investment strategy. In particular, central banks in many countries use the data to help make interest rate decisions. PMI surveys are the first indicators of economic conditions published each month and are therefore available well ahead of comparable data produced by government bodies.

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.