Many other private sector economists have also lowered their estimates of economic growth. Germany's Economic Union partners remain upbeat about continued economic expansion, as does Germany's machine tool industry federation. Machine tool orders are a leading indicator of cyclical swings and the federation reports a continued backlog of orders after record growth in 2000. Even though the federation is expecting a slight decrease in orders due to the U.S. slowdown, export demand from Europe is expected to continue to be strong. The article indicates that there is considerable disagreement about the future direction of the German economy.
Unemployment is considered to be a 'lagging' indicator of the business cycle.
Explain why this is likely to be the case.