importing average rating value

Hi guys,
I'm in the process of migrating my contents from xaraya to drupal, but now stuck while trying to import average voting values for each article into drupal.

I think in xaraya there is no table which store the users' vote value and node id, instead it only save the average rating and total vote per node. So, is there any table in drupal which I could set the initial average value for my imported nodes? I've looked into votingapi_cache table, but I think if I import/update the average and count values there, they will be overwritten whenever a user casts a new vote.

Thanks in advance