@Test
public void testSummary() {

  column1.appendCell("2013-10-23");
  column1.appendCell("12/24/1924");
  column1.appendCell("12-May-2015");
  column1.appendCell("14-Jan-2015");
  Table summary = column1.summary();
  assertEquals(4, summary.rowCount());
  assertEquals(2, summary.columnCount());
  assertEquals("Measure", summary.column(0).name());
  assertEquals("Value", summary.column(1).name());
}