Costa coffee and Premier Inn owner Whitbread ( LSE: WTB ) saw its stock peak three years ago and the share price is around 22% down since then. The rate of annual earnings growth slowed from chunky double-digit percentage increases starting with a two, down to single-digit figures, and I reckon the stock has been marking time to allow the firm's valuation to compress – a lower price-to-earnings (P/E) rating fits better alongside lower growth figures.