Abstract: A lightguide fiber (16), having predetermined losses, is fabricated from individual pieces (26) of fiber which are selected from an inventory thereof such that the median loss per unit length of pieces remains substantially the same after fiber fabrication. To fabricate the fiber, the inventory is first divided into a plurality of classes based on the following criteria: (1) whether each piece has a length above or below the average length of the pieces within the inventory. (2) whether each piece has a median loss per unit length above or below the median loss per unit length of the fiber to be fabricated, and (3) whether each piece has a variation in loss above or below a preselected value. Thereafter, the classes are successively examined, beginning with the first one, to determine whether any piece therein has transmission characteristics suitable for fabricating the fiber. If so, the piece is selected from the class.