The approach i've been using so far
is not for the faint-hearted :-)
The idea is to have (overlapping) LOD 'Frames'
to calculate the necessary values for all those Frames,
then use the results (at the Row Level) to fill the values into the (adjacent) rows.
This all is a FIXED LOD-heavy stuff, so the performance issues may occur.
Please refer to the recent thread for the similar problem / solution / discussion:
Please find the attached.
Hope it could help a bit.
USDA Question_v10.2_YF.twbx 1.4 MB