It’s a new year, and you’d like to do a year-over-year analysis showing if each customer bought more or less in 2009 than in 2008. This month, we’ll look at four different methods for building the report. Let’s say that you can gather an invoice register for 2008 on one work- sheet and an invoice register for 2009 on another worksheet. The structure of the report will vary depending on your system, but let’s assume that each report at least has a column for Customer Name and another for Revenue. Method 1: Pivot Table to Compare Two Lists Add a new blank worksheet to your workbook. Add three columns: Cus- tomer, Revenue, and Year. Copy the Cus- tomer and Revenue columns from the 2008 worksheet to columns A and B of the blank workbook. Fill column C with “2008” for all of these records. Below that data, paste the Customer and Rev- enue from the 2009 worksheet into columns A and B, filling column C with “2009” for all of those records. Choose one cell in your new data set. Select the Pivot Table command from either the Data menu (Excel 2003) or the Insert tab (Excel 2007). Click OK or Finish to create a blank pivot table. Drag the Customer field to the Row area, the Year field to the Column area, and the Rev- enue field to the Data Items area. To improve the report, remove the grand total column by unchecking Grand Total for Rows in the PivotTable Options dia- log. Add a Calculated Item called Delta, which calculates ‘2009’/‘2008’-1. In PivotTable Options, add a checkmark next to “For Error Values Show,” and leave the textbox blank to hide the division by zero errors. You now have a report as shown in Figure 1. Method 2: Pivot Table with Date Grouping This method works particularly well if your 2008 and 2009 columns are in the same format and if your data has an invoice date field. Copy the 2009 data (minus the headings) beneath the 2008 data. Choose one cell and add a pivot table. Drag the Invoice Date field to the row area. Right-click the first date and choose Group. In the Grouping dialog box, select both months and years. Click OK. The PivotTable Field list now offers a new virtual field called Years. Drag the Years field to the column area. Remove the Date field from the Row area. Add Customer to the row area. Add Revenue to the Data area. As in Method 1, you can remove the Grand Total for Rows from PivotTable Options. Since you’ve grouped the date field, however, you can’t add a calculated item to calculate the Delta. This calculation will have to be entered as a formula next to the pivot table. While building the formula, don’t point to cells using the mouse or the arrow keys. Instead, type the formula. Otherwise, you might get the annoying GetPivotData functions, which don’t copy well. Both methods 1 and 2 will fail if the combined data from the invoice registers contains more rows than your version of Excel offers. In that case, you can use the consolidation method. Method 3: Consolidation The Consolidation command works with a single column of labels in the left col- umn and any number of numeric fields going across. You can then consolidate multiple ranges. Excel will match up the 54 STRATEGIC FINANCE I January 2010 TECHNOLOGY EXCEL Year-Over-Year Analysis Using Excel By Bill Jelen