IOWA CITY — The percentage of University of Iowa students who graduated within four years fell in the most recent measure — moving the campus farther from its strategic goal for now despite a long-term trend toward improvement. The university, which has made timely graduation a key metric in its student success initiatives, reported to the Board of Regents a four-year graduation rate of 53 percent for the entering class of 2014, according to documents made public last week. That’s down from 55 percent for the 2013 entering class, and is 7 percentage points away from the UI goal of 60 percent by 2021, according to the university’s strategic plan. Iowa State University — which historically has been about 10 points or more below the UI in the four-year graduation category — reported an increase from 46 to 49 percent for the most recent measure, bringing it within 4 points of the UI — the closest since at least 2000. ISU also saw an increase in the percentage of students who graduate within six years — from 73 to 75 percent — while the UI saw a slight decrease from 74 to 73 percent.