Spent time with #Tableau calculated fields today. Created Product Value Category field & ran into problem - some products categorized as BOTH categories. Took a min to realize: transaction-level data means same product, different prices. Note to self: check data structure before building categories.

Σ Waterfall charts are perfect for showing both individual contributions & cumulative impact. Each bar shows how much each subcategory adds to total- you can instantly see which categories drive the biggest changes. Easy in #Tableau with calculated field (sales difference) #dataviz #LearningInPublic