Your roommates’ plants might be dying, but investors haven’t forgotten to water their portfolios this year. According to our latest Bear or Bull survey, 57.5% of investors are bullish heading into June despite the famous stock market adage, “Sell in May and go away.” Even the most bearish analysts have raised their S&P 500 forecasts as major US indices keep breaking new records.

• The S&P 500 and Nasdaq 100 are both up over 10% this year, with positive monthly returns in six of the past seven months.
• As of May 15, nearly $172B had flowed into US mutual funds and ETFs after two years of outflows.

Where do markets go next? With such substantial numbers, it’s hard to believe interest rates are at 23-year highs and over $6T is still in money market funds. So, what’s driving this rally? According to Apollo’s chief economist, foreign investors might be pouring money into US markets for its stronger economic outlook — or to capitalize on AI enthusiasm that’s lifting the markets. This leaves two key questions for investors: What happens if international markets become more attractive or if AI doesn’t deliver? And for the bulls, what will happen when interest rates drop, and money moves from money market funds to higher-yielding opportunities?