For a question that is so fundamental to emergency preparedness, this question is not easy to answer.
First, the question is very general. Do you mean how long should you be able to live out of your go bag, your bugout bag, your vehicle, or a fixed site like your home or a lifeboat property such as a retreat or bugout location?
Second, we cannot foretell the future. Emergency planners look to records of past emergencies and then try to predict exposure to future volatility and emergencies.
This methodology is deeply flawed because the little snippet of the past that emergency managers have data for is never long enough, so the number of hours or days FEMA has told Americans to prepare for ballooned longer as the nation experienced higher order Black Swans or events that planners failed to predict, that harmed us.
Managing Risk
Nassim Nicholas Taleb wrote about this his books: The Black Swan: The Impact of the Highly Improbable (Taleb, 2010), and Antifragile, Things that Gain from Disorder (Taleb, 2012), two great books for anyone serious about risk. Both books are just as applicable to emergency managers, survivalists, and healthcare professionals as it is to actuaries and risk managers, maybe more so.
The Great Turkey Problem
Taleb uses a section of Antifragile called “The Great Turkey Problem” (an adaptation of a metaphor from Bertrand Russell) to show how trying to predict future risk based on past performance can cause one to fall victim to a Black Swan. Here is a short excerpt:
“A turkey is fed for a thousand days by a butcher; every day confirms to its staff of analysts that butchers love turkeys ‘with increased statistical confidence.’ The butcher will keep feeding the turkey until a few days before Thanksgiving. Then comes that day when it is really not a very good idea to be a turkey.“ (Taleb, 2012)
So, where did the turkeys go wrong? Had their data window covered a full year, they would have understood what the butcher was up to, had they survived the event, but it was too short. An economist or risk manager from FEMA would read that and say, “Well their window was simply too short.” But the real problem is that mankind sucks at predicting the future. The only way you can avoid this pitfall is to stop trying to predict the future and become antifragile and generally well prepared. I have watched “Chicken Little” survivalists fail badly at attempted predictions for 45 years or so now and it’s painful to watch. Don’t fall for it.
I am not advising you to prepare for known vulnerabilities, but fortunately, for the most part, you need more or less the same knowledge, skills, things and network to grow stronger in response to most volatility, disorder and disasters instead of being destroyed by them.
Economists
“Well, if you just put your money in the S&P 500, you can’t go wrong!” The…