President Donald Trump’s first 100 days in office are the worst for the stock market for the start of a president’s four-year term since the 1970s.

For a while, the theory that Donald Trump would avoid doing anything that tanked the stock market—named the “Trump put” after an options contract that can protect traders from downside losses—seemed to have failed catastrophically.

Donald Trump promised Americans a “boom like no other” if they elected him president. But based on the stock market’s performance during his first 100 days in office, it depends on what you mean by “boom.