Limit up/ limit down levels
There are a series of specific bands in which a stock index’s price is allowed to move – taken from a reference of the average price in the previous five minutes. When talking about limit downs, if the price exceeds the lower band, trading is suspended for 15 minutes.
For tier 1 – which includes S&P 500-listed stocks, NMS securities and some exchange-listed products with a price greater than $3 – the band is set at a 5% decrease (or increase for a limit up) from the current price between the hours of 9.45am and 3.35pm.
However, between 9.30am and 9.45am, and 3.35pm and 4pm, the band is set at a 10% decrease (or increase for a limit up) from an average of the price in the previous five minutes. The full list of specifications for limit ups/limit downs on stocks and other exchange-traded products can be found below.