Contrarian view, the Broker Dealers need to close the week at or above cash market 2,900 so as to encourage the last of the MM account balances to transfer in. The big payday is Uber IPO and that can go anytime over the next 28 or so days, so it will be the Broker Dealer Banks judgement call on liquidity levels. I think it goes off before the risk of bad earnings forecasts sink things. Of course I am probably wrong and the outlooks will all be five star rated. But I am guessing the Broker Dealers will make way more on the big IPO's than they will on earnings, so that is why I think they will try to grab that cash rather than have retail buy more Apple etc.
By the way look at the bag holder charts out on the internet. Unreal but yes at these levels retail is buying in for the first time this year. As the old rule says, retail tends to buy the most at tops. Assumption on my part that Black rock's Larry Fink has once again called a top.