Seppin is right I don't know for sure but their are some indicators that you can watch. Bond yield curve inverting is one. Although there are some contrarians that are saying this time is different. The other big signal I look at is employment numbers in areas where raw materials are produced and refined. I've not done much reading on it but I've seen it as a leading indicator. Please take everything I saw with a grain of salt I'm not an economist I just try to keep up.