ASR, ACD and PDD explained

ASR: answer seizure ratio

ASR is the share of call attempts that are answered: answered calls divided by total attempts, as a percentage. It is the headline measure of whether calls are getting through to a person or a voicemail.

ASR depends heavily on the traffic itself. Dialer traffic to cold lists answers far less often than calls between customers who expect them, so compare ASR only between routes carrying similar traffic.

ACD: average call duration

ACD is total answered talk time divided by the number of answered calls. A sudden fall in ACD on a route that was stable often points to audio problems or calls being dropped, even when ASR looks normal.

PDD: post-dial delay

PDD is the time between sending the call request and the first ringing signal. Long PDD makes callers think nothing is happening and hang up, and it hurts predictive dialer pacing.

• Under 3 seconds is excellent for most destinations
• Over 6 seconds usually means a slow or overloaded route
• Mobile and some remote destinations are naturally slower

NER: network efficiency ratio

NER counts call attempts that reached the network successfully, including busy and no-answer outcomes, and excludes failures caused by the customer. A low NER alongside a normal ASR points to routing or network problems rather than a quiet destination.

Using the numbers

• Test each route with your own traffic before judging it
• Look at trends over days, not single calls
• Compare ASR and ACD together, not one without the other
• Ask for per-destination figures, not a single blended average