Global exchanges are changing trading rules to protect their markets from intense volatility and speculative trading as the coronavirus pandemic threatens the world economy.
Many markets have shortened trading hours, and others are mulling whether to follow suit.
Here are some of the measures taken by exchanges across the world so far:
The Reserve Bank of India cut trading hours for bonds and foreign exchange to four hours between April 7 to 17
India's market regulator halved position limits for certain stock futures, restricted short-selling of index derivatives and raised margin rates for some shares in a bid to curb "abnormally high" volatility.
The measures went into effect on March 23 and are set to continue for one month
On March 17, the Philippines became the first country to suspend trade only to reopen later that week after the government exempted financial trading platforms from a strict coronavirus quarantine procedures.
The country revised its circuit breaker rules that will last until the end of June
New rules will see a 8% drop trigger a 30-minute halt in trade; a 15% fall to initiate a 30-minute halt, while a 20% plunge will see it halted for an hour
Earlier in March, South Korea tightened short-selling rules for three months from March 11
Stocks with a sudden and abnormal increase in short-selling transactions will be suspended from further short-selling for 10 days, compared with a the current limit of one day
Stocks on the KOSPI that drop 5% or more and where daily short-selling transactions are up by three or more times the average of the previous 40 days will be subject to the new rule
The country's central bank and financial regulator to cut trading hours for the currency and stock markets
The stock exchange tightened circuit breaker rules, where a more than 5% drop on its main stock index will see trading halted by 30 minutes, compared with the 10% previously
If the index's losses extend to 10% when trading resumes, it will be halted for a further half hour
The exchange has also changed mechanisms for individual stock prices, and trading will now be halted if there is a 10% move, down from a previous 20-35%
There is also a ban on short-selling: the exchange removed all stocks on a list where it was allowed until further notice
The financial markets regulator banned short-selling on the Vienna stock exchange until April 18
The country's securities regulator banned short-selling on the Athens stock exchange until April 24 to shield the equities market from volatility
From March 17, market regulator Consob suspended short-selling on the Milan stock market for three months.
Imposed a one-month ban on short-selling, which it said could be extended.
France banned short-selling on 92 stocks on March 17
A ban on short selling has been in place in Turkey since late February following an air strike that killed dozens of Turkish troops
The Johannesburg Stock Exchange decided against shortening trading hours, but its head said JSE would strictly enforce rules prohibiting uncovered, or naked short-selling and lengthen the mandatory halts to trading circuit breakers.
United Arab Emirates
Shares in the United Arab Emirates stock exchanges will be allowed to drop a daily maximum of 5% from their previous day closing price, state news agency WAM reported.