Free to paid apps ratio

[i2m]

We need your help on the the following question:
There are round 100k apps and 2 bn downloads.
1. How many downloads count for free apps?
2. How many apps are free apps?

Your estimates or links to survey and data is highly welcome.

Thanks

[Jibrano]

Hmmm...would be interesting to know the pricing dynamism of the App Store.

I read some stuff and estimates vary but i would like to learn more opinions too.