The ornamental design for a decorativetire, as shown and described.
FIG. 1 is a perspective view of a decorative tire of the present invention; the dotted lines demonstrate a wheel the tire is mounted on are for illustrative purposes, no claim is being made for the dotted lines that make up the wheel;
FIG. 2 is a perspective view of the decorative tire thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is a right side view thereof; and,
FIG. 6 is a left side view thereof.
The broken line showing of environment is for illustrative purposes only and forms no part of the claimed design.