title: What are the units for OpenTSDB's Rate function?
body: <p>Let's say I have a byte counter metric that increments once per second. If I plot it, I will get a monotonically increasing plot. The Y-axis is labeled 'bytes'.</p>
  
  <p>I want to plot the rate of change of my counter, so I click the "Rate" checkbox. Rate is change per unit time, but what is that unit? What label should the Y-axis have?</p>