6 GOOLSBEEANDKLENOW Table3: DistributionofAdobeRevenue(%) Householdgoods 27 Apparel 27 ICT 19 Recreationgoods 14 Foodandbeverages 7 Othergoodsandservices 3 Transportationaccessoriesandparts 2 Medicinesandmedicalsupplies 1 Notes: Entries are the percent of total Adobe revenue in each of the CPI Major Groups, averaged from 2014 through 2017. Source: Authors’ calculations using Adobe Analytics and BLSdata. 3 DPIvs.CPIInflation Weconstruct a matched-model price index using the Adobe data, and call it the Digital Price Index (DPI) to distinguish it from the CPI. We start with price changes for overlapping products in months t−1 and t. These are products selling positive quantities in both months. We take log first differences of average unit prices. To aggregate price changes across products within an ELI, weuseTornqvistweights. Thesearetheaveragespendingshareoftheproduct in the ELI in months t−1 and t. The spending shares are based on Adobe data 2 for overlappingproducts. Tofacilitate comparison with the CPI, we aggregate the Adobe ELI inflation ratesusingtheCPIrelativeimportanceweightsforeachELI-month. Weusethe samesetofELIstoconstructbothourcomparisonCPIandtheDPI.Inthisway 2Like the BLS, we do something special for apparel. We construct a simple index of average unitprices. Thisistoavoidextremedeflationfromfashionandseasonalcyclesforclothing.