It depends on what the definition of depression is. We have to remember that modern macroeconomics is still a new field (having started during and largely because of the Great Depression). With very little experience with depressions and their effect on the global economy, even the best minds are just guessing. To quote Terminator 2, "The future, always so clear to me, had become like a black highway at night. We were in uncharted territory now, making up history as we went along."