"During the “glut” era of the 1970s and ’80s, American demand for more expensive, older bourbon was so low that much of it was bottled and exported to foreign markets, notably Japan." I found this a little comical, because during this time, Japan was establishing its own bourbon whiskey. A lot of the people he asked said about 8 years was a good number, so they must have come up with that number through trial and error before.