Each rule defines behaviour in both directions. Direction is taken from the level ranks, so aggregation and disaggregation are one operation:
Details
sumUp: sum. Down: split proportionally to the weight. For extensive quantities (capacity, demand, area, population).
weighted_meanUp: weight-weighted mean. Down: copy unchanged. For intensive quantities (efficiency, price, capacity factor).
meanUp: unweighted mean. Down: copy unchanged.
copyUp: the common value, erroring if it is not constant. Down: copy unchanged. For region-invariant scalars.