The first half of 2022 was the worst first half for the stock market since 1970.

Judge on the S&P 500 price index as the standard measure of "the stock market". True: the S&P 500's percentage change from 31 Dec 2021 to 30 Jun 2022 was the worst first-half performance since the first half of 1970, with no first half between 1971 and 2021 worse. Mostly true: it was the worst since 1970 on the S&P 500 but not on another major index, or it was the worst since a year within about one year of 1970. Mostly false: it was among the worst first halves but a first half between 1971 and 2021 was worse on the S&P 500. False: the first half of 2022 was not an unusually bad first half, or several later first halves were worse.

Set before the research began.

1. E1 Stocks close their worst first half in 52 years, here’s what you need to know | CNN Business CNN · 30 June 2022

   “The S&P 500 printed its worst half-year since 1970, the Dow had its largest first-half drop since 1962 and the Nasdaq had its largest percentage drop ever.”

2. E2 Stocks close their worst first half in 52 years, here’s what you need to know | CNN Business CNN · 30 June 2022

   “The S&P 500 (SBSPX) has posted its worst first half in more than 50 years, dropping 20.6% during the first 6 months of 2022.”

3. E3 2022 stock market decline - Wikipedia Wikipedia

   “In the first 6 months of 2022, the S&P 500 fell 21%, the worst 6-month start to a year since 1970.”

4. E4 Investors have endured a brutal six months The Irish Times · 12 July 2022

   “The S&P 500 sank 20 per cent, its worst start to a year since 1970.”

CNN reports that the S&P 500 fell 20.6% in the first six months of 2022, its worst first half in more than 50 years and its worst half-year since 1970 (E1, E2). Wikipedia and The Irish Times separately describe this as the S&P 500's worst start to a year since 1970 (E3, E4). These independent sources all agree that no first half from 1971 to 2021 was worse on the S&P 500, which meets the criteria for true.