Avamar & DPA Reporting

Hi

I am have customer who is using Avamar Grid & Node at mutiple location from past 3 years .

Every year he buy new node or Add Node into exiting Avamar  Grid & at same time backup Manager is not able to provide justification about node upgrade & not able to show the report to management  to help Bckup Manager   & to understand data growth along with new data  ingestion  reality I had install DPA server at customer  site but when i am trying to pull report of Old dates ( Before DPA Installed ) report is not getting display in DPA .I do Have following queries

1. Does DPA start reporting from the day it has installed ?

2. what is process where by i will ble to pull old logs from avamar & import into DPA so that DPA will able to analyze same.

Prasad