Upper/lower circuit

hi, cn someone pls explain the price band of a stock is calculated on previous day close price ? or is it today opening price (in case its gap dwn or gapup)

eg. in todays hatsun, nse site showing price band as 20 n lwr band is 623 n upper is 935 n yestrday close is 1040 … if we deduct 20% frm yestrday closing price it comes to be 832 thn why is it 623 ?

also today it went down by more than 20% …ws trading at 824 fr quite sometime thn why it dint hit lwr circuit ?

if lwr band is 623 acc to nse site thn how is it calculated … if calculated on todays opening price too it comes 707 nt 623 …pls clarify !!

Lower and Upper Circuit is calculated based on previous day’s close.

Hatsun has announced Bonus in ratio of 1:3 and it today went ex-bonus so price of the stock today corrected to factor in the bonus shares issued, as price corrected to factor in the corporate action it didn’t trigger the circuit limit.

ok, Thank you !!