Sub-series consists of indexes and registers created by the Treasury Board itself to constitute true finding aids to the Minutes of decisions. For the period 1868-1948, they give an accurate and condensed account of the Board's decision on each submission. The first numerical sequence starting with a zero extends from May 1869 to March 1870. The present numerical sequence began in 1870. In the first method of indexing (previous to 1948) the submissions were passed on receipt to the Register Clerks, who entered on the Register in handwritten form the name of the person signing the submission, the date of receipt, and the subject. The submission was then indexed by department and by name in a second register, and by subject in a third. The submissions themselves were then grouped according to subject and were forwarded to the appropriate officials. In 1948 a new system was inaugurated and it lasted until June 1965. Instead of registers, a combined index and progress card system was used to record the information relating to submissions to the Treasury Board. The surviving card index cannot be used for subject searches. It was designed by the Treasury Board as a specialized cross reference tool for use where the number of the Treasury Board Minute is already known from other documentation. With the correct Treasury Board decision number, the card index may be used to determine the exact date of approval. This date is required to locate the decision file in the Sub-series Decision Files and Board Book. The cross reference card also indicates if there is related correspondence which may appear in Sub-series Gray Volumes, and Sub-Series Special Subject Registry of Decision Correspondence. The card index is, therefore, the key to cross referencing and locating related documents in four parallel Sub-Series: Minute Files, Board Books, Gray Volumes and Special Subject Registry of Decision Correspondence.