I understand derating based on bundling and temperature, but how does conduit size come into play. NEC states 16 #12AWG in 3/4 emt based on 40% fill. Bundling adjustments decrease the ampacity of #12 THHN to 15A based on 10 - 20 conductors in a raceway and 21A based on 7 - 9 conductors in a raceway. Does this mean that if I run a 1 1/2" emt that I can only pull 7 - 9 #12 current carrying conductors through it! I hope someone can clear this up since its been a pretty hot topic for arguments on the job.