How to Add Up All That Gets Made in the United States

National income is the number that to day we call g d p gross domestic product. It was invented because there was clearly a perception that there was something really, really bad going on but they didn't really know what i mean. Adding up all this stuff is harder than it may sound. You just have to figure out everything that you need to count. And pretty soon you can't turn on the radio without hearing these new numbers and what they're measuring, this new thing called the economy.