Does anyone know how many Amps the starter motor uses to start a Mk 4, 1.6, 16V engine, each turn of the key.

Having a small problem with a new battery, the voltage is dropping to 11.5 Volts over a period of a few days, could it be the fact that I only drive the car half a mile on a daily basis. The charging system is OK. Seems to be OK if I do a run of 40 miles.