This post descibed a typical accounting problem regarding monthly data and IMHO should be of interest to readers of this group. The OP posed a ( to him ) a simple question. As usual answers to simple questions are usually much more complicated than expected by the initial poser. If the OP had more knowledge he would have known ( or at least thought ) that there was no answer to his question ...but angels go where devils fear to tread. His question motivated an answer describing a basic solution provided by AUTOBOX . If one has an abundance of time on his or her hands then the solution provided by AUTOBOX could be programmed in R or SAS ... saving that one might be better advised to reach out and exploit already existing functionality available in existing software.
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