During his time there he played 15 matches out of 23, so missed a third of their fixtures.
At the time Barnsley were 9th with 34pts from 23 games (1.47ppg). They'd won 10, lost 9 and drawn 4, scoring 27 and conceding 29.
Since he left they're now 7th, having played 9 and got 17pts (1.88 ppg)...