sortOptions = (new Map([
["solar, natural gas, nuclear, coal, wind, hydro, other", ["solar","natural gas", "nuclear","coal", "wind", "hydro", "other"]],
[categories.join(", "),
categories],
["alphabetical (default)",
["coal", "hydro", "natural gas", "nuclear", "other", "wind"]],
["most to least by usage",
sortedByTotal],
["least to most by usage",
sortedByTotal.slice().reverse()]
]))