code: function (d, chart, series) {
              var returnCy = 0;
              if (series.y.measure !== null && series.y.measure !== undefined) {
                  returnCy = series.y._scale(d.cy);
              } else if (series.y.categoryFields !== null && series.y.categoryFields !== undefined && series.y.categoryFields.length >= 2) {
                  returnCy = (series.y._scale(d.cy) - (chart._heightPixels() / series.y._max)) +  dimple._helpers.yGap(chart, series) + ((d.yOffset + 0.5) * (((chart._heightPixels() / series.y._max) - 2 * dimple._helpers.yGap(chart, series)) * d.height));
              } else {
                  returnCy = series.y._scale(d.cy) - ((chart._heightPixels() / series.y._max) / 2);
              }
              return returnCy;
          }
docs: Calculate the centre y position