Breaking his silence over the current global meltdown, Tesla CEO Elon Musk on Friday said the recession the world is now experiencing owing to multiple macro-economic factors could last up to 18 months. "Based on past experience, about 12 to 18 months," Musk replied to a follower who asked him about how long he thinks this recession will last. "Companies that are inherently negative cash flow (i.e. value destroyers) need to die, so that they stop consuming resources," he added.