A multi-layer co-extruded film includes a first layer having a first color and a second layer having a second different color, wherein the first and second layers are co-extruded layers. The multi-layer co-extruded film also includes a plurality of intermittently stretched regions, wherein the multi-layer co-extruded film exhibits a perceivable color change when subjected to a strain. In perceivable color change or E between about 2.50 and about 7.00. Methods of forming a multi-layer co-extruded film includes coextruding a first layer having a first color with a second layer having a second different color and intermittently stretching a plurality of regions of the multi-layer co-extruded film, wherein the first layer and the second layer are co-extruded and intermittently stretched to exhibit a perceivable color change when subjected to a strain.