i = adjubi
function adjusts the upper bound of the century month code
(CMC) of an event based on an interval. It is generally used to calculate the maximum previous
date of birth based on a date of birth and a minimum number of months allowed between births.
The lower_cmc1 and upper_cmc1 arguments are numeric expressions generally representing the date of birth CMC range of the child that was born prior to the child represented in upper_cmc2. The lower_cmc2 argument is not used (but is used by adjlbi). The upper_cmc2 argument is a numeric expression generally representing the date of birth CMC of a child. The interval argument is a numeric expression expressing the minimum number of months between events, which is generally the minimum number of months allowed to pass between a woman's successive childbirths.
The function returns the adjusted upper bound of the CMC of an event based on the number of months represented by the interval. If the adjusted upper bound is less than lower_cmc1, the function returns the error code of -1. It the adjusted upper bound is otherwise valid, the function returns either the adjusted upper bound or upper_cmc1, whichever is less.
t = adjubi