Help understanding the output from lame

Here’s an freeze-frame output from lame while encoding using variable bitrate on Ubuntu:

LAME 3.98.2 32bits (http://www.mp3dev.org/)
CPU features: MMX (ASM used), SSE (ASM used), SSE2
Using polyphase lowpass filter, transition band: 17249 Hz - 17782 Hz
Encoding pj2007-08-05d1t03.wav to pj2007-08-05d1t03.wav.mp3
Encoding as 44.1 kHz j-stereo MPEG-1 Layer III VBR(q=4)
    Frame          |  CPU time/estim | REAL time/estim | play/CPU |    ETA
  3500/10289  (34%)|    0:05/    0:15|    0:06/    0:19|   16.994x|    0:12
192 [3481] %%%%%%%%%%%%%%%****************************************************************************************************************
224 [  11] %
256 [   7] %
320 [   1] %
----------------------------------------------02:57---------------------------------------------------------------------------------------
   kbps        LR    MS  %     long switch short %
  192.3       12.1  87.9        95.9   2.1   2.0

Specifically regarding this:

192 [3481] %%%%%%%%%%%%%%%****************************************************************************************************************

What does the ratio of % to * mean?  It shifts around as the encoding progresses.  Is it something like “placeholder for 100″ or something?