Respuesta :
Think the best explanation to this that the trends in the law of supply and demand could affect the value of prices. If the demand is high but the supply is controlled or few the possibility is that the price will increased drastically due to the demand. If the demand will low and the production is high the prices where eventually low also.
Don't know how to explain but the higher the population demand the higher the price the lower the demand the lower the price example if 60% of the u.s population want Nike this is demand