N.H. Rev. Stat. Ann. § 82:2

Every railroad, railway, express, and every parlor, sleeping or dining car company, or other company not a railroad company owning any cars operated for profit on any railroad in this state shall pay to the state an annual tax, as of April 1 of each year, upon the market value of its property and estate, at a rate equal as may be to the average rate of taxation at that time upon other property throughout the state.Market valuemeans the property's full and true value as defined in RSA 75:1.