Your best estimate of our national debt on January 1, 2015 would be Naim 21:44 Economics Chapter 12 Your best estimate of our national debt on January 1, 2015 would be a. 9 trillion b. 12 trillion c. 15 trillion d. 18 trillion e. 21 trillion Answer: D Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+