Spot bitcoin (BTC) exchange-traded funds (ETFs) in the U.S. added $552.78 million on Thursday, their fourth consecutive day of inflows.

That's the longest run since Aug. 28 and the joint-longest since the seven days ended Aug. 14, which coincided with bitcoin's ascent to an all-time high of over $123,000. Wednesday's $757.14 million net inflow was the largest for a single day since July 16, .

Spot ether (ETH) ETFs are also . Thursday marked a third straight day, and followed six consecutive days of outflows during which more than $1 billion was withdrawn.

Both the underlying assets experienced rallies in the latter half of the week, benefiting from by the U.S. Federal Reserve on Sept. 17.

Bitcoin has risen nearly 3.2% in three days to sit just above $115,000, . Ether has in to reclaim the $4,500 mark.