Multiple cities in California, New York and Washington will have a minimum wage at or above $15 an hour in 2019. The minimum wage hikes include legally mandated annual adjustments to keep up with inflation, laws passed by state legislators and voter-approved ballot initiatives. Congress hasn’t increased the federal minimum wage of $7.25 an hour since 2009, and its purchasing power has eroded due to inflation by more than 10 percent since then. Some business advocates warn that a minimum wage set too high can discourage hiring and lead companies to relocate to neighboring cities or states with lower minimum wages. Minimum-wage proponents say many businesses that employ low-wage workers are in sectors such as food service and hospitality, where jobs aren’t easily moved and businesses need to remain near their customer base.