Investors returned from a long holiday weekend to find stocks had continued the push from Friday, breaking back above levels not seen since March, as hope blossomed amid the reopening of the economy, a potential coronavirus vaccine, and the breaching of technical levels in stock indexes.

The S&P 500 climbed 1.9%, breaking above 3,000 for the first time since March 5, although has fallen off some since achieving its best gains as of 1230pm EST. The Dow Jones Industrial Average rallied 2.4%, also pulling back from its high Tuesday, but rallied above 25,000 at one point for the first time since March. The Nasdaq Composite advanced 1.5% and was less than 4% removed from a record set in February, but has since sold off considerably amid weakening moves from Netflix, Microsoft, and Adobe.

Stock Index ETFs are advancing Tuesday as well, tracking moves in the benchmark stock indexes. The SPDR S&P 500 ETF Trust (SPY), has rallied 1.85%, the SPDR Dow Jones Industrial Average ETF (DIA) is 2.25% higher, while the Invesco QQQ Trust (QQQ) is holding 0.43% gains, after moving higher earlier in the day.

A number of factors are at work in driving markets higher, including optimism over the U.S. economy reopening, and hope for the development of coronavirus vaccine.

U.S. biotech company Novavax said Monday it commenced the first human study of its experimental coronavirus vaccine and anticipates initial results on safety and immune responses this summer. The Novavax announcement comes after biotech Moderna drove markets higher last week after it reported sanguine development news related to its vaccine trial where all 45 participants had developed coronavirus antibodies. There are now 10 vaccines in clinical evaluation and 114 in pre-clinical evaluation, according to a survey by Fundstrat.

The S&P 500 exceeded its 200-day moving average for the first time since March 6, as it burst through the 3000 level, reaching nearly 3020 in the futures overnight Monday. A plethora of technical analysts view that moving average as a sign of the long-term trend, and therefore transitioning above it could signal a change in long-term trend from bearish to bullish.

The S&P 500 has also continued to hold the 61.8% retracement of the move from all-time highs to the March lows, another potentially bullish development for technical analysts. Although a v-shaped development has been dubious, according to many analysts, some strategists are now changing their minds.

“As of this writing, the virus appears to be coming under control,” said Bruce Bittles, chief investment strategist at Baird, in a note to clients. “Lockdowns have been relaxed and we have not seen a resurgence in the virus.”

“A return to a bull market in stocks and a return to economic growth are dependent in large part upon the containment of the virus which will allow businesses to re-open and consumers to resume their spending habits,” said Bittles. “The market seems to be pricing in a quick economic recovery (V-shape) which would help explain the recent rally.”

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