Are Economic Forecasts of any Value or Usefulness?

Why do financial markets rise and fall with every announcement of how a country's economy fared? Why does the media consult economists for their views, and why do views invariably differ, sometimes by quite a lot? Singapore's Ministry of Trade and Industry forecasts the Singapore economy to grow between 1- 3% for 2016. Is this information useful? A 2% admission of possible margin of error is a lot. 2% of Singapore's GDP of about US$300 billion is US$6 billion. Enough to give each of our 3.27 million citizens US$1,834.00 So what is the value of economic forecasting particularly when it is always being revised up and down as the situation changes? Rationale for still coming out with forecasts: 1. No matter how unreliable macroeconomic forecasts are policy makers still need to have forecasts for decision-making and planning. They cannot rule out the uncertainty but they can do Scenario Planning viz. if scenario A, then do this scenario B then do that. 2. At leas...