Great article (subtitled: What economists can’t tell you about the most isolated country on Earth) on the North Korean economy by Marcus Noland.
While the best quote comes at the end of the article (“Former U.S. Vice President Walter Mondale once counseled me that anyone who claims to be an expert on the North is a liar or a fool.”), the piece is an excellent reminder on the scarcity of accurate data coming out of the North. Take a look if you have time – a 10-minute read.