title: Core-Plot: Keep offset between x-axis and its axis labels constant when using autoscale (plotSpace:scaleToFitPlots)
body: <p>In my scatter plot, I use Core-Plot's autoscale feature, which seems to work fine, according to my test plots (see below): </p>
  
  <pre><code>CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)graph.defaultPlotSpace;
  [plotSpace scaleToFitPlots:[NSArray arrayWithObject:sharePricePlot]];
  [valuationPlotSpace scaleToFitPlots:[NSArray arrayWithObject:valuationPlot]];
  
  CPTMutablePlotRange *xRange = [plotSpace.xRange mutableCopy];
  CPTMutablePlotRange *yRange = [plotSpace.yRange mutableCopy];
  
  [xRange expandRangeByFactor:CPTDecimalFromDouble(1.0)];
  [yRange expandRangeByFactor:CPTDecimalFromDouble(1.0)];
  plotSpace.xRange = xRange;
  plotSpace.yRange = yRange;
  </code></pre>
  
  <p>I use custom labels for my x-axis which I set in an standard enumeration. In this enumeration, I set each axis label based on the demo app as follows:</p>
  
  <pre><code>CPTAxisLabel *newLabel = [[CPTAxisLabel alloc] initWithText:[NSString stringWithFormat:@"%u", year]
  textStyle:xAxis.labelTextStyle];
  newLabel.tickLocation = CPTDecimalFromUnsignedInteger(idx);
  newLabel.offset = 0;
  [xAxisLabels addObject:newLabel];
  </code></pre>
  
  <p>However, even though I set the offset to 0, which should position the labels very close to the x-axis (in my view), the offset between the axis and the labels is different depending on the range of y-values (please refer to the charts for Amazon and Priceline below). </p>
  
  <p>How can I set the <strong>distance between the x-axis and the labels independent of the (auto-scaled) y-values?</strong></p>
  
  <p>Chart 1: Amazon
  <img src="https://i.stack.imgur.com/9oJ50.png" alt="Amazon"></p>
  
  <p>Chart 2: Priceline
  <img src="https://i.stack.imgur.com/s2Z8S.png" alt="Priceline"></p>
  
  <p>THANK YOU!</p>