Now you can see the average pace for each lap but it should be nice that you can also see the cumulated pace and speed after each lap. The cumulated speed after lap 2 is the average speed of lap 1 + lap 2 together. For example
lap1 avg speed=15kmh,
lap2 avg speed=10kmh
lap1 *** speed => 15kmh
lap2 *** speed => 12,5kmh
That way you can easily see for the example the average speed after each 5km in a 20km race