Orange-juice futures in New York are heading for a 15th straight day of losses, the worst rout in records back to 1967.

U.S. demand for the juice has been weakening for years. Add that to a declining citrus crop in Florida, the top domestic grower, and you’ve got a recipe for shrinking investor interest as fewer people want to use futures to hedge. Prices have slumped about 17 percent this month.

The liquidity drain has also sapped market swings: 60-day historical volatility for most-active futures is at the lowest since November 2014. Even though Florida’s harvest is forecast by the government to drop to the smallest in 73 years, surging imports of frozen concentrate juice from suppliers like Brazil and Mexico are making up for the losses.