function commaValue(amount)
  local formatted = amount
  local swap = false
  if formatted < 0 then
    formatted = formatted*-1
    swap = true
  end

  while true do
    formatted, k = string.gsub(formatted, "^(%d+)(%d%d%d)", '%1,%2')
    if k == 0 then
      break
    end
 end

  if swap then
    formatted = "-"..formatted
  end
  return formatted
end