The earliest Nancy Drew books were published as dark blue hardcovers with the titles stamped in orange lettering with dark blue outlines and no other images on the cover. The covers went through several changes in early years: leaving the orange lettering with no outline and adding an orange silhouette of Nancy peering through a magnifying glass; then changing to a lighter blue board with dark blue lettering and silhouette; then changing the position of the title and silhouette on the front with black lettering and a more "modern" silhouette. Nancy Drew is depicted as an independent-minded 16-year-old who has already completed her high school education (16 was the minimum age for graduation at the time); the series also occurs over time, as she is 18 by the early 1940s. Apparently affluent (her father is a successful lawyer), she maintains an active social, volunteer, and sleuthing schedule, as well as participating in athletics and the arts, but is never shown as working for a living or acquiring job skills. Nancy is affected neither by the Great Depression—although many of the characters in her early cases need assistance as they are poverty-stricken—nor by World War II. Nancy lives with her lawyer father, Carson Drew, and their housekeeper, Mrs. Hannah Gruen. Some critics prefer the Nancy of these volumes, largely written by Mildred Benson. Benson is credited with "a feisty spirit into Nancy's character." The original Nancy Drew is sometimes claimed "to be a lot like [Benson herself – confident, competent, and totally independent, quite unlike the cardboard character that Stratemeyer had outlined."