code: function adjustTickAmount() {
  
  			if (maxTicks && !isDatetimeAxis && !categories && !isLinked) { // only apply to linear scale
  				var oldTickAmount = tickAmount,
  					calculatedTickAmount = tickPositions.length;
  
  				// set the axis-level tickAmount to use below
  				tickAmount = maxTicks[xOrY];
  
  				if (calculatedTickAmount < tickAmount) {
  					while (tickPositions.length < tickAmount) {
  						tickPositions.push(correctFloat(
  							tickPositions[tickPositions.length - 1] + tickInterval
  						));
  					}
  					transA *= (calculatedTickAmount - 1) / (tickAmount - 1);
  					max = tickPositions[tickPositions.length - 1];
  
  				}
  				if (defined(oldTickAmount) && tickAmount !== oldTickAmount) {
  					axis.isDirty = true;
  				}
  			}
  
  		}
docs: When using multiple axes, adjust the number of ticks to match the highest
  number of ticks in that group