Fra premierleague.com

"The Actim Index is the official player rating system of the English Premier League and Coca-Cola Championship. It was introduced for the 2004/05 season and was devised by statisticians at the University of Salford in partnership with PA Sport. In the 2006/07 season the Actim Index was enhanced by the addition of assists and clean sheets to the factors that are taken into account."

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"If during this pass, an opposing player significantly alters the speed or direction of the ball, then no assist is given except if this intervention directly results in an own goal.

If a goalkeeper does not have control of the ball and parries a shot or drops a cross or the ball rebounds off the woodwork, the attacking player shooting or crossing the ball receives the assist if a goal directly ensues.

In the event of a penalty, the player earning the penalty gets an assist if it is successfully scored, but not if he takes it himself in which case no assist is given. No assist is given for a player who earns a free kick that subsequently results in a goal."