Is it possible to refer to particular elements of loop-and-merge data, in particular elements not part of the current loop?

That is to say, if Im on the n-th loop of a loop-and-merge question, then ${lm://Field/1} refers to the n-th element of the first column of my data. Is there a way to refer to, say, the n-1-th element? I know that I could just save it as some embedded variable during the n-1th loop, but I’d ideally like to refer to any value in the entire loop-and-merge data conditional upon the choices of the survey taker. So this would get unwieldy. 

Thanks for any advice!