The bonds of the officers named in G.S. 58-72-10 shall be carefully examined on the first Monday in December of every year, and if it appears that the security has been impaired, or for any cause become insufficient to cover the amount of money or property or to secure the faithful performance of the duties of the office, then the bond shall be renewed or strengthened, the insufficient security increased within the limits prescribed by law, and the impaired security shall be made good; but no renewal, or strengthening, or additional security shall increase the penalty of said bond beyond the limits prescribed for the term of office.
N.C. Gen. Stat. § 58-72-20