Python

Linear continuation vs. damped Holt-Winters, walked forward over 36 held-out periods. The winner’s margin is thin enough that a library convention flips it — so the page shows both methods and says so out loud.

A budget workbench in Excel: four template workbooks, six VBA macros for reconciliation, variance, and the close checklist — plus Python twins of the two computational macros so every number reproduces headlessly.