The brief window of optimism that followed the US-Iran ceasefire is closing fast. Oil shipments through the Strait of Hormuz, which had recovered to roughly 50% of pre-war levels under the June 17 memorandum of understanding, have fallen sharply over the past week as the ceasefire arrangement fell apart and active fighting resumed between US and Iranian military forces. According to Goldman Sachs, flows through the strait have dropped back to an estimated 3 to 5 million barrels per day, down from approximately 10 million barrels per day in early July.