Over the weekend, while looking through some US coins with my sons and nephew, my oldest son asked me that question. Embarrassed that I didn't know the answer, we took to the internet and found a few explanations. The best was a Coin Week article from 2012 (link posted below). I found it to be very interesting reading about a tough time in our nation's history and how it impacted coinage... thought some of you may find it interesting as well. Happy reading. http://www.coinweek.com/numismatic-history/the-missing-years-collecting-the-coins-of-1931-to-1933/
