I am using the American commuinty survey dataset and I have two numerical variables COSTELEC "annual cost of electricity" and COSTFUEL "annual cost of heating". I would like to combine these two variables for every household in the set and use them as one variable, but I have no clue how to do that.

Also after combining them, I would like to estmiate the proportion of that new variable "energy costs" from another variable HHINCOME "Annual income".


I would appreciate the help I am a beginner and I have this stata assignement for my final and I am struggling to get it done.

Thank you