The register of deeds shall record all the facts reported to the register of deeds under N.H. Rev. Stat. § 80:64, 70, 75 and 76, and any other facts required to be reported by the tax collectors of his or her county in an acceptable recording method. He or she shall keep an index thereof showing the location of the property and the names of the owners to whom taxed, the names of delinquents, the holder of the real estate tax lien, and the names of those who pay delinquent taxes or redeem from the real estate tax lien. The index may be the same as that for other records in the office or a separate one, as each register shall determine. All documents received by the register from the tax collector shall be returned to the tax collector within 30 days.