A voltage is induced across a conductor moving in a magnetic field. The same thing will happen to a stationary conductor kept inside a varying magnetic field. A varying magnetic field can be created by a moving magnet.
The peak values of the induced voltage are displayed, -1.66 V and 1.84 in this case.
The voltage starts getting induced on the coil when the magnet approches. It increases to a peak value and then starts reducing. This is bcause the two poles will have opposite effect. When the magnet is exactly at the centre, the voltage is zero. After that the effect of pole entered second starts dominating.
Note that the second peak is larger than the first one, because the velocity of the magnet increases during the time interval between the two peaks.