Auto filter problem

Hello,

when i am filtering any item for adding value in that item, it will gets filter but the blank cell coming at last is much further behind then overall last blank cell.

For example i have prepared an excel in which i am giving sequnce numbering for particular code like FG ,BFL etc. presently i have blank cell no 450,Now when i am filtering BFL for adding sequnce number in that the last blank cell i am getting is 10475 instead of 450 which is the last overall blank cell. this will result in lots blank cell between overall excell enteries.


Please suggest some idea what to do for that