Bug 210635 Incorrect preview of chart after reverse categories.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/computation/withaxes/PlotWith2DAxes.java
}
			else if ( ( iType & NUMERICAL ) == NUMERICAL )
			{
				if ( ( iType & PERCENT ) == PERCENT )
				{
					oMin = new Double( 0 );
					oMax = new Double( 100 );
				}
				else if ( ( iType & LOGARITHMIC ) == LOGARITHMIC )
				{
					oMin = new Double( 1 );
					oMax = new Double( 1000 );
				}
				else
				{
					oMin = new Double( -1 );
					oMax = new Double( 1 );
				}
			}
		}
		if ( iType == DATE_TIME )
		{
			try
			{
				return new Calendar[]{
						asDateTime( oMin ), asDateTime( oMax )
				};
			}
			catch ( ClassCastException ex )
			{