You're right about the mix. After earthquakes I've found that some places will still stay open, but it's cash and maybe no change or maybe checks are OK. So I have mostly $1.00 and $5.00 bills with some $20.00. Remember no power means no Banks, ATM's, cash registers or gas stations and most large markets will close. After the Loma Prieta quake I know people that drove about 50 miles to find a working ATM. ( and get gas, ice, food,water, clean up supplies, batteries, etc)