In general the PTC measures graduation in three different ways:

Measures of graduation that are on an absolute time scale indicate the semester a student graduated in terms of a calendar year (e.g., September 1st, 2008). [In other words, a student with graduation date of 9/1/2008 is a student who graduated at the end of the fall 2008 term]

For the majority of analyses, relative-scale, cumulative graduation measures are preferable. These measures indicate, at a given point of time relative to entry to college, whether or not a student has graduated at some point between entry and that point in time. That is, a four-year graduation measure will indicate if a student earned a degree within four years from graduation. For that same student, a six-year cumulative graduation measure will also completion in that time period, even though the time it took the student to graduate was shorter than six years.

Relative-scale, cross sectional measures of graduation indicate whether or not a student graduated at a particular point in time relative to their point of entry to CUNY. Thus for a student who graduates in eight semesters, their value for graduating in semester eight will indicate completion but their value in semester twelve will not indicate completion. These measure have been used for sequence analysis in the past.

The measures of graduation that do not involve a time scale indicate whether or not a student ever got a degree within the time frame of the data set.

It should be noted that the graduation rates produced by the PTC will not match those published on OIRA's website. This is due to differences in the way that the PTC measures entering cohorts and is to be expected.


The absolute time scale measures in the PTC include:

The relative-scale, cumulative graduation measures in the PTC include:

The cross sectional relative-scale measures include:

The measures of graduation that do not include a time scale are: