private void UpdateForecastCells()
        {
            List <Cell> cells = CellRepository.GetCells(ForecastSheet, Periods.Select(p => p.Id)).ToList();

            if (cells.IsNullOrEmpty())
            {
                return;
            }
            List <(Guid entityId, Guid periodId, decimal fact, decimal potential)> data =
                Calculate(cells, Periods);

            data.ForEach(d => {
                CellRepository.SaveCell(ForecastSheet, d.entityId, _factIndicatorId, d.periodId,
                                        new ValueInfo {
                    Value = d.fact
                });
                CellRepository.SaveCell(ForecastSheet, d.entityId, _potentialIndicatorId, d.periodId,
                                        new ValueInfo {
                    Value = d.potential
                });
            });
        }