I noticed a huge difference between Mediabase and Nielsen BDS.

"Young" leads Radio Songs for a fourth frame with 137 million audience impressions (up 1%). As of this week on Nielsen BDS, used by Billboard as the official airplay source.

Now to Mediabase:

1. FUN. - We Are Young f/Janelle Monae: 185.501 (+ 0.210)

You see the HUGE difference? Almost 50m difference. I guess it's not that reliable to use Mediabase for any estimations...

The same thing goes to all other songs. ->

2. GOTYE - Somebody That I Used To Know: 150.754 (+ 3.531)

Radio helps fuel the sustained stratospheric sales of "Somebody," as the song adds top Airplay Gainer honors on the Hot 100 for a second week. It rises 6-3 on the Radio Songs chart with 106 million in all-format audience (up 24%), according to Nielsen BDS

Source: http://www.billboard.com/news?utm_so...06941552.story

You just have to multiply the Mediabase figure by 0.75 and there you have an approximation to BDS numbers.

This have been explained before.. You don't have to open a thread for it

Because Nielsen and Mediabase are two different monitoring services. Nielsen (what Billboard uses) does not monitor as many radio stations as Mediabase does, so by that logic, Mediabase numbers are always going to be higher since they can detect more "audiences" from the extra radio stations that they're tracking vs. Nielsen.

BDS is the most reliable. Mediabase is so out of reality. Especially after the changes last March.