Problem with counters of sapscript

hii frnds

i need to print some data in the last page of my script . the data should be only in the main window . the problem is in main window we cant use counters of script like nextpage , page , formpages cauze these r not gvng true values .this gives true values in variable window . so can any body suggest how to do it . are there any other counters which gives last page no of the script inside the main window .

thanking you

rohit gupta