Composite leading indicators (CLIs) summarise information on early signals contained in a number of key short-term economic indicators known to have a leading relationship with GDP. The direction of their growth indicates the likelihood of an expansion or a slowdown in future economic activity for individual countries or groups of countries.

The OECD has been compiling CLIs for 29 member countries, for six OECD non-member economies and for 7 country groupings, e.g. G-7 countries, since the 1980s. The CLI comprises a set of component series selected from a wide range of key short-term economic indicators (224 in total, about 5-10 for each country). Those selected are known to provide an indication of future economic activity.

Compared to traditional quantitative statistical surveys, business and consumer tendency surveys present many advantages as a source of short-term economic information. They collect information which is easier for enterprises and consumers to supply because the answers are not based on precise records and the returns can be submitted more quickly.

Tendency surveys cover a wide range of variables selected for their ability to monitor the business cycle and include information on variables not covered by quantitative statistics, e.g. capacity utilisation and views on overall economic situation.