I'm reasonably well stocked on ammo, food and water for an estimated 3 months. So even if I overestimated by 6 weeks, I still have 6 weeks of supplies. We just added 4 or 5 items to the cart each time we shopped since about 2006, with a few dry spells off and on. I have a lot of dry goods and some of the mountain house #10 cans. Baby formula is our big hole in our preps.