An economic decline is just one disaster that preppers seek to prepare for. When the economy falters, unemployment and poverty can run rampant and crime will escalate. Desperate people will be forced to do desperate things in order to survive. As the prices of necessary commodities rise, the buying power of the dollar shrinks. As central banks the world over print more currency, and introduce it into the economy, the purchasing value of that currency goes down. As the national debt increases the dollars value decreases.
Additional reasons for economic decline include debased currency, inflation, declining credit rating, failed stimulus plan, unwieldy entitlement programs, unions and lobbyists, pork barrel projects, government subsidies, over-regulation, illegal immigration, the complexity of derivatives, and escalating debt which results in higher taxation and a lower standard of living.
You can see all 5 of my post apocalyptic fiction books, 2 of my zombie fiction books and 1 of my horror fiction books on the left side of my blog page. Go ahead and purchase one or more over at Amazon.com. They are really quite interesting and entertaining to read if I do say so myself.