you have to go through each trade to see the quantity affected by the rules. there is no easy answer
say on Feb 15 you buy 10 shares of X in your IRA. on Feb 28 you sell 100 shares at a loss in your investment a/c. on Mar 10 you buy 25 shares in your investment a/c and 25 shares in your IRA.
you now have a wash sale on 60 shares the loss that would have been allocated to the 35 shares purchased in the IRA is lost forever. while the 25 shares purchased in your investment a/c get a portion of the wash sale loss added to what was paid.
or say on 10/15 you sell 100 shares at a loss in your investment a/c. the day after and for the next 9 trading days you purchase 10 shares a day in your investment a/c. since all the purchases occurred within the 31 day period the entire loss on the 10/15 sale is a wash sale. so each of the 10 purchases gets a portion of the wash sale added to their basis
if you use an American broker, it is required to determine the reporting for the wash sales. with foreign brokers you are on your own.
