Description
FPPREVDTCMC reports the century month code (CMC) for the date when the woman started using her previous contraceptive method.
Century month codes (CMC) are particularly useful for checking the consistency of dates, calculating intervals between events, and imputing dates when the information for an event is missing or partially complete.
Century month codes (CMC) are calculated by multiplying by 12 the difference between the year of an event and 1900. The year 1900 was chosen as the reference period because all of the DHS-relevant events occurred during the twentieth or twenty-first centuries. The month of the event is added to the previous result.
CMC = (Year minus 1900) * 12 + Month
For example, the CMC for June 2002 is:
CMC = (2002 minus 1900) * 12 + 6 = 1230
In other words, 1,230 months have elapsed between January 1900 and June 2002. Starting with CMC figures, one can calculate the month and year using the following formulas:
Year = int( ( CMC minus 1 )/12 ) + 1900
[int(x) is the integer part of x]
Month = CMC minus ( ( Year minus 1900 ) * 12 )
For more information, visit The DHS Program website to find the latest Guide to DHS Statistics.
