This is the third appearance for Fox on the Run (per the DB) and its third different year--previously it showed up in 75 and 76, once each. However '74 is the year it was released, so I'm not sure how DM got away with spinning it in those other years.
ETA: Looks like the chart activity rule comes into play here. Fox didn't chart 'til late '75, so it appears to be legal in three different years.