The ornamental design for an adjustablestoragebin, as shown and described.
FIG. 1 is a perspective view of an adjustable storage bin;
FIG. 2 is a rear elevation view thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a right elevation view thereof;
FIG. 5 is a left elevation view thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The broken lines in the drawings depict portions of the adjustable storage bin that form no part of the claimed design.
The adjustable storage bin is shown with a symbolic break in its length. The appearance of any portion of the article between the break lines forms no part of the claimed design.