JASA impact factor - by topic

["Bruno L. Giordano" <bruno.giordano@xxxxxxxxxxxxxxx>]

Dear list,

I have one curiosity about the impact factor of The Journal of the 
Acoustical Society of America: has it ever been computed separately for 
each of the topics (e.g., psychological acoustics; transduction etc.)?

Differences would make sense because different research areas likely 
have different publication rates.

Thank you,

	Bruno