20 stamps/page * 5 pages. You got 100 stamps in total.
Background: This Happy Birthday stamp conveys exuberant greetings by calling to mind the childhood excitement of a birthday party. Each of the five letters in the word "HAPPY" is inspired by a different party decoration in the midst of a flurry of multicolored ribbons and confetti. This stamp was designed by Lisa Catalone Castro and Rodolfo Castro, featuring a digital illustration by the latter. Ethel Kessler served as art director.