Hello,
I agree with Jasmine Li, there is not standard functionality.
But you can use Enchancement points.
go to tr. SE38 -> SAPLFVW_SECURITY_ACCOUNT
then open INCLUDE LFVW_SECURITY_ACCOUNTI01
then find MODULE pai INPUT
there is variable sec_acc_dynpro-rldepo - this is your sec. acc. number. You have to fill it in order to get running Securities Account.
Inside MODULE pai INPUT you can't use Enchancement points.
But inside PERFORM d0100_pai_start you can use it. And variable sec_acc_dynpro-rldepo is avaiable to fill.
inside PERFORM d0100_pai_start press button
"Enchance (Shift+F4)".
Then go to menu "Edit -> Enchancement Operations -> Show implicit Enchancement Options"
then iside PERFORM d0100_pai_start you'll notice lines of " symbols. This is the place where you can add your code to perform running numbers of sec. account.