N.H. Rev. Stat. Ann. § 31:94-d

Towns, cities, and counties which have adopted the provisions of RSA 31:94-a may incur debt under the provisions of RSA 33 in an amount not to exceed 1/3 of all taxes assessed on April 1 of the year following adoption of RSA 31:94-a, excluding payments upon outstanding debts, said debt to be discharged in not more than 20 years. For the purposes of this section, taxes assessed shall include all taxes reimbursed to the town, city or county in accordance with the provisions of RSA 31-A. Debt incurred pursuant to this section shall not be included in the debt limit of the town, city or county, and the funds borrowed pursuant to this section shall be used only to defray additional costs that result from the adoption of an 18 month transitional accounting period.