Going by Boeing's orders page, it seems that for any cancellations/conversions of orders, they just decrease the number from the current year's totals.
For example, listed on the page currently are:
-4 x 744s cancelled/converted into 77Ws for PR
-2 x 777s converted into 787s for AC
They take these numbers off this year's totals to get a "net orders" count. Wouldn't it be more accurate and reflective of yearly orders by adjusting orders in the year that they were first made?
For example, in whichever year those 4x PR 744s were ordered, an adjustment to the yearly count for that year could be made and displayed.
Does anyone know why they do this?