“We are in a bear market,” Morgan Stanley equity strategist Michael Wilson told clients in a Monday report, CNN reports. The banking giant has been issuing negative warnings since at least April. Wilson pointed out that more than 40% of the S&P 500 is down 20% or more. Definitions vary, but the usual metric is when a mix of stock indices have dropped an average of 20% over two months.

He also flagged the fact that the stock market no longer bounces back after week-long average declines like it did from 2002 to 2017. “The only years the Buy the Dip hasn’t worked was during bear markets, or the beginning of one,” Wilson wrote.

Goldman Sachs is more positive, suggesting on Friday that the S&P 500 still has room for growth of around 6% this year. “Volatility is not the same as a sustained bear market,” Erik Knutzen, the firm’s multi-asset chief investment officer, wrote in the report.

Investors looking to protect themselves against the possibility of a maturing bear will have to adapt to many new conditions in the market since the last extended declines, almost a decade ago, write Jen Wieczner and Scott Decarlo in Fortune’s 2019 investor guide. For one thing, new tariffs and inflated stock prices make traditional large capitalization companies look less like refuges. In fact, embracing volatility may be the way through this next stretch: One investor quoted in the guide wants to profit from the volatility by investing in financial firms that take a cut of market transactions.