Old wallet backup resumes blocks in a clean wallet?

[bitcedo]

4 days ago I downloaded blocks for my wallet who had keyloger and I used my old Wallet GUI backup (8 mouths old) in that blocks. I formated my computer but yesterday i downloaded a refresh wallet the rcp and the GUI version. I opened the GUI version with my old wallet and I have 80% completed and saw 3 peers. But if I create a new wallet with the GUI version I only have like 2% or 4%. This is normal? yesterday I made a bootscan with my avast and dont found nothing. I have malbytesware too and dont found nothing. If is normal i can use my backup without problems?