The index closed at 9,918 on 20 March and 9,894 on 23 March, its first closes back below 10,000 since the crossing, in a quarter in which Brent rose from $72 to above $110 (FTSE Russell closing values; ICE Brent settlements).
Resolves YES if the official FTSE 100 closing value published by FTSE Russell (LSEG) is below 10,000.00 on any trading day from 5 January to 3 April 2026 inclusive. Intraday lows do not count. If that source has not published in time, the closing value as reported by two of Reuters, the Financial Times and BBC News settle it.
Three of four earlier milestones were lost within a year. We looked at each time since 1998 that the FTSE 100 first passed a new thousand-point level. We asked whether it closed back below that level within a year. Round numbers pull on markets. They bring selling to lock in gains, and they fill the headlines.