"A group of physicists at a university in Vienna wanted to explore how the complexity of musical styles changes over time. They measured complexity according to the varieties of instrumentation in different styles, rather than considering rhythm or harmony, but the results are nonetheless interesting. By this measure, folk has always been among the most complicated genres. The group also found that more complex music does not sell as well — which could be because major labels demand a certain amount of consistency and uniformity when they offer artists financial support, or because a simpler musical approach is more broadly accessible."
But of course, folkies (and we do not mean introspective navel-gazing monotone beathy chord bangers, charted here as "acoustic", we mean real folk musicians) already knew this.
Read the paper at http://arxiv.org/pdf/1405.5057v1.pdf