My dashboard says forty orders today but my statement says thirty-eight. Which one is right?

Both, and they are counting different things. Order counts on the Dashboard include every order, cancelled ones too, while revenue there counts only orders that were not cancelled. The monthly statement separates them: orders placed, delivered and cancelled each get their own line, so thirty-eight is most likely placed minus cancelled. Money is worked out the same way on both screens, at what was actually charged, in your own timezone, so revenue never disagrees. If you want the day's orders with the cancelled ones visible, open the orders board for that date and use the filters.