I have downloaded and used Audacity to capture and paste together two sides of audio voice tapes.  It has been excellent for that and I am impressed with its operation.  However, I was disappointed when I tried to save off an MP3 file that I had recorded at 32 Kbps and discovered it had been re-inflated.  I checked under Preferences, File Formats, MP3 Export Setup and to my dismay I could not set the export bitrate below 56Kbps.  Is there any plan to lower the export bitrate?  Export bitrates of 32 and 24 Kbps would be very useful for my application. 
Thank you for your help.
Ken Pearson