(a) Base Offense Level:
(1) Level from §2T4.1 (Tax Table) corresponding to the tax loss; or
(2) 6, if there is no tax loss.
For purposes of this guideline, the "tax loss" is the tax loss, as defined in §2T1.1, resulting from the defendant’s aid, assistance, procurance or advice.
(b) Specific Offense Characteristics
(1) If (A) the defendant committed the offense as part of a pattern or scheme from which he derived a substantial portion of his income; or (B) the defendant was in the business of preparing or assisting in the preparation of tax returns, increase by 2 levels.
(2) If the offense involved sophisticated means, increase by 2 levels. If the resulting offense level is less than level 12, increase to level 12.