hi pix.
i think that Drop/Erlang is more accurate for this case.
any way,suppose this situation:
Drop/Erlang=0.639999985694885
TCH Traffic=23.4300003051757
HTCH T raffic=18.1299991607666
Defined Tch=Avail Tch=22
Avail HTCH=43
TCH MHT=13.43
Call attempt TCH=2164
NOTE:this measurement is done in 1 Houre.
according your formula,what is number of drop calls in this 1 houre?