Interest rates; underpayments and overpayments. The rate of interest determined under section 6621 of the Code for the calendar quarter beginning April 1, 2007, will be 8 percent for overpayments (7 percent in the case of a corporation), 8 percent for underpayments, and 10 percent for large corporate underpayments. The rate of interest paid on the portion of a corporate overpayment exceeding $10,000 will be 5.5 percent.

Fringe benefits aircraft valuation formula. The Standard Industry Fare Level (SIFL) cents-per-mile rates and terminal charge in effect for the first half of 2007 are set forth for purposes of determining the value of noncommercial flights on employer-provided aircraft under section 1.61-21(g) of the regulations.

LIFO; price indexes; department stores. The January 2007 Bureau of Labor Statistics price indexes are accepted for use by department stores employing the retail inventory and last-in, first-out inventory methods for valuing inventories for tax years ended on, or with reference to, January 31, 2007.

Temporary and proposed regulations under section 368 of the Code provide additional guidance regarding the qualification of certain transactions as reorganizations described in section 368(a)(1)(D) where no stock and/or securities of the acquiring corporation is issued and distributed in the transaction.

Temporary and proposed regulations under section 368 of the Code provide additional guidance regarding the qualification of certain transactions as reorganizations described in section 368(a)(1)(D) where no stock and/or securities of the acquiring corporation is issued and distributed in the transaction.

Weighted average interest rate update; corporate bond indices; 30-year Treasury securities. The weighted average interest rate for March 2007 and the resulting permissible range of interest rates used to calculate current liability and to determine the required contribution are set forth.

A list is provided of organizations now classified as private foundations.

The IRS has revoked its determination that American Education Foundation International of San Francisco, CA, and Ladder 12 Firefighters Fund, Inc., of New York, NY, qualify as organizations described in sections 501(c)(3) and 170(c)(2) of the Code.

This procedure provides issuers of qualified mortgage bonds (QMBs) and qualified mortgage credit certificates (MCCs) with average area purchase price safe harbors for statistical areas in the United States and with a nationwide average purchase price for residences in the United States for purposes of the QMB rules under section 143 of the Code and the MCC rules under section 25. Rev. Proc. 2006-17 obsoleted in part.