// Get Current Row So We Know Where To Start From.
                int currentRow = excelWorksheet.Dimension.End.Row;

                string campaignDate = string.Join("", sourceExcelPackage.Worksheet(DATABASE_1_WORKSHEET).Select(x => x["CAMPAIGN_DATE"].Value));

                // Start The Real Work.
                foreach (var row in sourceExcelPackage.Worksheet(EVENT_1_WORKSHEET))
                {
                    // CustomerID
                    string customerId = row["CustomerId"].Value.ToString();

                    // Create Report Object To Help Keep Things Readable.
                    ReportObject reportObject = new ReportObject
                    {
                        EventType = row["EventType"].Value.ToString(),
                        DateCreated = row["DateCreated"].Value.ToString(),
                        EmailType = row["Context"].Value.ToString(),
                        LinkClicked = row["Destination"].Value.ToString(),
                        CampaignDate = campaignDate,
                        SupporterID = string.Join("", sourceExcelPackage.Worksheet(DATABASE_1_WORKSHEET).Where(x => x["DSM_CustomerID"] == customerId)
                                                                                                        .Select(x => x["SUPPORTER_ID"].Value)),

                        PathwayStageHistoryOID = string.Join("", sourceExcelPackage.Worksheet(DATABASE_1_WORKSHEET).Where(x => x["DSM_CustomerID"] == customerId)
                                                                                                                   .Select(x => x["PATHWAY_STAGE_HISTORY_OID"].Value))
                    };

                    // Add Next Row.
                    currentRow++;

                    // Assign Data Here.
                    excelWorksheet.Cells[currentRow, 1].Value = reportObject.SupporterID;
                    excelWorksheet.Cells[currentRow, 2].Value = reportObject.CampaignDate;
                    excelWorksheet.Cells[currentRow, 3].Value = reportObject.EmailType;
                    excelWorksheet.Cells[currentRow, 4].Value = reportObject.DateCreated;
                    excelWorksheet.Cells[currentRow, 5].Value = reportObject.EventType;
                    excelWorksheet.Cells[currentRow, 6].Value = reportObject.LinkClicked;
                    excelWorksheet.Cells[currentRow, 7].Value = reportObject.PathwayStageHistoryOID;

                    // Return the current row as we may
                    // use this to build some sort of progress.
                    yield return currentRow;
                }