progressbar = ProgressBar::Base.new(:output         => output,
                                    :total          => 33,
                                    :title          => 'My Title',
                                    :progress_mark  => 'x',
                                    :remainder_mark => '-',
                                    :length         => 92,
                                    :rate_scale     => lambda { |rate| rate * 200 },
                                    :throttle_rate  => 12.3)
# Make some progress updates over a period of time
progressbar.to_h

{
  'output_stream'                       => #<StringIO:0x007fdf2d056928>,
  'length'                              => 92,
  'title'                               => 'My Title',
  'progress_mark'                       => 'x',
  'remainder_mark'                      => '-',
  'progress'                            => 22,
  'total'                               => 33,
  'percentage'                          => 66.66,
  'elapsed_time_in_seconds'             => 599.99994701264,
  'estimated_time_remaining_in_seconds' => 400,
  'base_rate_of_change'                 => 0.03672787979966611,
  'scaled_rate_of_change'               => 7.345575959933222,
  'unknown_progress_animation_steps'    => ['=---', '-=--', '--=-', '---='],
  'throttle_rate'                       => 12.3,
  'started?'                            => 2012-07-26 12:50:00 -0500,
  'stopped?'                            => false,
  'finished?'                           => false
}