Comment by thaumasiotes

Yes, in air freight weight and volume are independently significant.

But I'm not saying that all multidimensional data can be losslessly reduced to a one-dimensional value. That would be crazy! the point of my comment is that it isn't true that -- as the parent comment asserted -- it is impossible to usefully report multidimensional data with a one-dimensional value. To the contrary, it is quite possible that the multidimensional data adds zero value over the one-dimensional summary.

Some multidimensional data can easily be losslessly reduced to a one-dimensional value. We can easily make a much stronger claim -- all one-dimensional values are "reductions" of other, multi-dimensional characterizations of the same data. But they're not all useless! The number of dimensions you use to describe data is an editorial choice, mostly unrelated to the raw facts.