1961. Reprint. 159 pages. Blue dust jacket over blue cloth with gilt lettering. Black and white graphs throughout. Light tanning to pages; more prominent to text block edges. Pen and pencil inscription to front free endpaper. Binding remains firm. Boards have minor corner bumping and edgewear with light marking overall. Spine has light sunning with soft crushing to ends. Lettering remains bright and clear. Unclipped dust jacket with minor rubbing, chipping and tearing to edges. Moderate tanning to edges and visible scuffing overall.