The value of a trading card depends on a combination of the card's condition, the subject's popularity and the scarcity of the card. In some cases, especially with older cards that preceded the advent of card collecting as a widespread hobby, they have become collectors' items of considerable value. In recent years, many sports cards have not necessarily appreciated as much in value due to overproduction, although some manufacturers have used limited editions and smaller print runs to boost value. Trading cards, however, do not have an absolute monetary value. Cards are only worth as much as a collector is willing to pay.