Examples may be in you installed model already /models/<modelName/<versionNum>/views/subroutines/TemplateViews/levelORIntensiveVarProjection_v4.t
The template for this type of variable does 1 variable only and gives you several options on how to project it.
Currently those options include:
If you have a non-standard projection time horizon (i.e. not beginning in the first year of simulation, and not based purely on a trend from history) then adjust
local varHis[upperdims,timeseq] local varBckGnd[upperdims,timeseq] local varResult[upperdims,timeseq]
varHis spans the time from which you might want to build the trend, and
varResult spans the projection time.