century_break

Default: 50
Range: 0 – 99 or -1

The dms_subtypes in the 30s, 60s, and 90s have a 2-digit year value (yy) which represents dates in the 20th and 21st centuries. Values < 50 are 21st century years (20yy); values >= 50 are 20th century years (19yy). When the century_break value is set to 50, yy = 1950–2049. When the century_break value is set to 11, yy = 1911–2010. When the century_break value is set to -1, the century break value is dynamically calculated based on the current year giving the two digit years a range of current_year - 49 to current_year + 50. In the case of 2012, this range is 1963 to 2062.

You can find DMSII date formats that are affected by the century_break parameter at Decoding DMSII Dates, Times, and Date/Times.