As gold prices rise, miners have been boosting shareholder payouts in the face of a decline in global output. That’s worrying some investors concerned about the long-term growth prospects of an industry built on a depleting resource. The value of gold, a haven commodity, is driven more by global economics than supply and demand. Any unexpected event — from a surprising cure for coronavirus to a positive trade deal — could drop the value significantly. High prices put more gold scrap on the market, low ones increase hoarding and, if miners’ output remains static, so should profits.