Joseph:May be it can help. For more than a decade I’ve been using the following relationship for peak hour traffic calculations.
It’s been certified by ITU and also by tons of real data provided by many telcos around the globe.
The simple equation goes as:
BHC = ASR * BHCA where
BHC: Busy Hour Calls :Switch OUTPUT
BHCA: BHC Attempts:INPUT at switch
ASR: Attempting Seizure Ratio (or the probability of getting al call through the switch).
Tipically ASR is between 60% to 80%. I use tipically 70%.
The calls stopped at the switch are grouped on 2/3 major factors:
1- B User Busy (about 8%-10%)
2- B User doesn’t answwer (same)
3- Network Congestion (the rest)
At Europe, Japan and USA ASR is above 80% for long distance and 85% for local calls.
The remaining countries average a 65%. This can be used with PABX.