Designing for human variability (DfHV) requires efficient allocation of sizing and adjustability. This can preserve product performance while reducing some measures of cost. For example, specifying only as much adjustability as necessary for a desired level of accommodation leads to devices which are better suited to their users and more cost efficient. Similarly, when multiple sizes of an adjustable artifact are to be produced, specifying only as many sizes as are necessary, with an appropriate amount of adjustability per size, leads to a set of products that cost less, require fewer unique parts, facilitate maintenance standardization, and ease inventory control. An alternative to the standard procedure of evenly dividing size ranges is considered wherein an equal degree of accommodation per size is also presented. A simple example related to exercise bicycle seat height is discussed.