The oil price halved in March from $50 to $25pb as a result of excess supply due created to the spat between Saudi Arabia and Russia. This happened at a time when production should have been cut due to the coronavirus pandemic. The price fall created a 5% increase in demand for crude oil despite the lack of end use . In reality demand for tankers was much higher as traders filled vessels with crude for floating storage.
By the end of April the gains in March are undone as land storage facilities were nearly full. So demand then falls back just 5%. During the same month refinery runs fall approximately 15% while overall global demand for oil products was even lower. During this month the price of oil falls even lower to $20pb.
By the end of May the oil price starts to recover to $35pb as production cuts take effect and we therefore expect further falls in underlying demand to take effect, similar to the decrease in refinery runs.