What's changed and unchanged for IKEA pencils through the years?

Context: IKEA pencils are small pencils provided for free in IKEA stores worldwide. They are found in small boxes attached to poles, together with maps, measuring tapes and shopping forms. The IKEA pencil has been known for the wide variety of designs. Through the years the color changed from blue, to yellow to the natural color of wood. Despite the different colors, its dimensions have always been 7×87mm. Their common in-store application is for notetaking, with customers making note of selected items from product tags onto their notepads and visiting the self-service furniture warehouse to collect their showroom products in flat pack form, using their notes to locate their products.

Answer: The color changed from blue, to yellow to the natural color of wood. The dimensions of the pencil has never changed which is always 7 x 87mm.