The Periodic Table Of
Business Process Outsourcing

The metrics of a contact center are the important parameters to determine its performance. Whether it is about the customer satisfaction rate or an agent’s performance on call, measuring these metrics is important to determine whether the contact center will be able to attain the desired goals and the corrective measures required (if any).

To help you understand better, we have categorized these metrics into six different sections - agents, call, technology, call center, customer and communication. Take a look at the periodic table shared below and you will be able to gain a clear understanding of the same.

Call Quality (RTA)

 Refers to how your agents handle your customer calls.

Real Time Adherence (RTA)

A metric which compares planned agent activity to actual activities throughout the day

Unpaid Time Off (UTO)

An authorized absence from work without pay for ten (10) consecutive workdays or less, which may be granted for medical or personal

Avg Concurency Chat (AC)

Indicates the average number of concurrent chat sessions an agent has open at any given time.


 The time for which people are paid during which they are not available to handle calls.

Schedule Adherence (SA)

Metric revealing whether or not call center agents are adhering to their assigned schedules.

Net Promoter Score (NPS)

The metric for assessing customer loyalty for an organization's brand, products or services

Controlled Busies(CB)

It refers to the ACD’s capability to generate busy signals when the queue reaches a threshold of taking back up much more than it has been programmed for.

Agent Productivity(AP)

A metric that measures the amount of work accomplished during a specified time frame (sometimes called output or efficiency).

Idle Time(IT)

Metric that defines the time spent by agents ready and waiting to take calls.

Agent Not Ready(ANR)

The amount of time spent while an agent processes customer requests while not speaking to a customer.

Call Load(CL)

The number derived after multiplying the sum total of average talk time and average after-call work with call volume for a particular period of time. This number is also referred to as workload.

Call Arrival Rate(CAR)

Refers to the average number of incoming calls during a particular period of time. Knowing this rate helps in determining the number of calls that are to be answered or put on hold during a particular time.

Average Time to Abandonment(ATA)

Refers to an average amount of time for which the callers wait in queue before abandoning.

On-call Rate(OCR)

Refers to the amount of time spent by an agent on call as compared to the time spent on taking notes, filling surveys and possibly being delayed.

Longest Call Hold(LCH)

This refers to the longest duration of time for which a caller was put on hold before getting connected with a call agent.

Peaked Call Arrival(PCA)

It is a surge of traffic beyond random variation within a short period of time.

Repeat Calls(RC)

This refers to the number of calls that were related to a common issue or subject. It helps determine the topic that has been a common matter of concern to many.

Predictive Dialing(PD)

An automated system to place outbound calls and deliver answered calls to agents. The number is placed back in the queue in case the dialer detects busy signals, answering machines or no answer.

Scheduling Exemption

This is the stage when an agent is involved in an activity other than the normal, planned schedule.

True Calls Per Hour (TCH)

This refers to the number of actual calls handled by an individual or group divided by the occupancy for that period of time.

Self-Service Usage(SSU)

This metric is used to track whether the customers are using the self-service options and how many times did it end the need of getting in touch with an agent. Tracking its usage is helpful in determining the need of revisiting your IVR set-up.

Visible Queue (VQ)

It is a type of queue that keeps its callers informed about its length and the expected time for which they might have to wait.

Virtual Call Center(VCC)

This is a type of scattered call center that works as a single site to handle calls and update reports.

Flushing Out the Queue(FOQ)

This refers to introducing a change in the system thresholds so that the callers waiting in a queue for an agent group are redirected to another queue with available agents or shorter waiting queue.

Customer Retention Rate (CRR)

It is the percentage of customers that stay with your business as compared to those you had at the start of the journey. Effective in improving the company’s growth and revenue, the process of customer retention begins with the customer’s first contact with the company and continues throughout the lifetime.

CRR can be calculated by subtracting the number of new customers acquired during that period from the number of customers at the end of a particular period. This number should, then, be divided by the company’s total number of customers at the start and then, multiplied by 100.

Cost per Call (CPC)

Cost incurred by the call center to call the customers for a particular period of time. CPC can be calculated by dividing the total operational cost of the firm by the total number of calls made by the allocated resources during a given period of time.

Call Completion Rate (CCR)

It refers to the number of calls that were connected successfully in comparison to those that failed. This rate can be calculated by dividing the total number of successfully connected calls during the day/hour by the total number of calls that were ate attempted during the data.

Average Wait Time (AWT)

Also known as Average Speed of Answer (ASA), AWT refers to the length of time it takes for a customer to connect with an agent and get his/her need addressed. It includes both the calls that are handled directly by the live agents and those that are addressed solely by the IVR.

Agent Schedule Adherence (ASA)

The rate or an average amount of time in which an average amount of calls are required to be answered by the service vendor within a certain amount of time. As per the experts, the ASA of any contact center should not exceed 28 seconds.

Average Speed of Answer (ASA)

It is the rate or an average amount of time in which an average amount of calls are required to be answered by the service vendor within a certain amount of time. As per the experts, the ASA of any contact center should not exceed 28 seconds.

Average Call Transfer Rate (ACTR)

It signifies the number of calls that were transferred to a different department, supervisor or queue due to lack of competent support or adequate information. Call transfer generally leads to higher customer dissatisfaction as their query remains unsolved or is made to wander in the same queue.

All Trunks Busy (ATB)

It indicates the number of times and the total time for which all trunks were busy in a particular trunk group. However, this does not reveal the number of callers who got busy signals when trunks were busy.

Agent Group

Also known by various other names like split, gate, queue and skills group, this refers to a collection of agents who share a common skill set, such as an ability to handle customer complaints.

Agent Attrition

Responsible for handling incoming and outgoing calls, an agent is the one who is known by names like customer service representative (CSR), telephone sales or service representative (TSR), associate, consultant, engineer, operator, technician, account executive, team member, customer service professional, staff member, attendant and specialist.

Abandoned Call Rate (ACR)

Refers to the number of callers who hung up the phone even before the agent could answer their call. Lengthy wait times and a poor IVR system are the most common causes of high ACR.

Calls per Hour (CPH)

Refers to the number of calls answered by an agent in an hour. Generally calculated as the total volume of the calls handled by the call center, determining this number for different agents enables an easy identification of high-performing and low-performing agents. This, in turn, helps in determining the need of taking measures like imparting training, implementing new rules, etc.

Peak Hour Traffic (PHT)

It refers to that time of the day when your call center receives the maximum calls from the customers. Determining this metric helps in keeping the requisite team prepared so that it is able to handle the entire upcoming load from the callers.

Online-to-Schedule (OLTS)

The number of minutes for which an individual was logged-on as compared to the actual duration for which he/she was required to be logged-on. Factors like breaks taken off-schedule, not-ready, make-busy, and logged-out are not included in its computation. However, factors like talk time, idle time, and post-call wrap-up time are included.

Transferred ACD Calls

The Transferred ACD number is the sum of all the calls the agent Transferred or Conferenced while on an active ACD call. The number increases when the Transfer or Conference is complete.

Outgoing Calls (Non-ACD-Trunk)

The total number of calls outgoing on this route. These are non-ACD calls, but could include outgoing calls made from the DN keys of the ACD agent positions.

Outgoing Non-ACD Calls

The number of outgoing calls from an agent position using extension (DN), conference, or transfer keys.


One hour of telephone traffic in an hour of time. For example, if circuits carry 120 minutes of traffic in an hour, that's two Erlangs.

Erlang C

Calculates predicted waiting times (delay) based on three things: the number of servers (reps); the number of people waiting to be served (callers); and the average amount of time it takes to serve each person.

Erlang B

A formula developed by A.K. Erlang, widely used to determine the number of trunks required to handle a known calling load during a one hour period.

Enhanced ACD Routing

An optional ACD feature that allows supervisors to regulate ACD traffic and to give different RAN and music treatments to calls queued at the same ACD queue.

Caller-Entered Digits (CED)

Digits callers enter using their telephone keypads. The ACD, VRU, or network can prompt for CEDs.

Call Control Variables(CCV)

The set of criteria the ACD uses to process calls. Examples include routing criteria, overflow parameters, recorded announcements and timing thresholds.

WorkForce Management (WFM)

The art and science of having the right number of agents, at the right times, to answer an accurately forecasted volume of incoming calls at the service level standard set by the call center.

Silent Monitoring (SM)

A process that permits a supervisor to listen to both sides of a conversation including an agent and a caller. Used for determining training needs and performance quality. Neither agent nor caller is aware that the monitoring is taking place.

Session Initiation Protocol (SIP)

Is a communications protocol for signaling and controlling multi-media communicated sessions such as voice and video calls.


The waiting line for delayed calls. A queue holds the call until an agent is available.

Private Branch Exchange (PBX)

A private branch exchange located on the users’ premises and connected to the public network via trunks. Sometimes known a PABX where ‘a’ stands for automatic.

Load Balancing (LB)

The process of balancing contacts between multiple sites, queues or agent groups.

Integrated Services Digital Network (ISDN)

Is a set of telecommunications standards and implies to various types of communication services such as voice calls, video calls, packet-switched or data-switched data and fax transmission that can be done through this network.

Dialed Number Identification Service (DNIS)

Is a telecommunications service sold to corporations that allow them to determine which number a customer dialed to reach them. This service is important for companies that have different numbers for different services even though all the calls are handled by the same call center.

Computer Telephony Integration (CTI)

Connects a call center’s computer system to the agent’s phone system and integrates with the acd or dialer to help the agent identify and access customer details when on a call with the customer.

Call Routing (CR)

A process designed to ensure that each call is routed to the right agent with the right skills to handle the call. This feature is mostly to route high-end customer calls to a shorter queue.

Voice Over Internet Protocol (VOIP)

Is a technology that allows telephone services to be delivered over the internet. It uses facilities, such as digital data packets to deliver voice information over the internet. It can be a popular choice, as VOIP service providers are normally offered at a lower cost than traditional phone companies.


A single transmission channel between two points, both of which are either switching centers or nodes, or both.

Speech Recognition (SR)

The capability of a voice processing system to recognize and translate human voice signals into digital signals a computer system can understand.

Screen Pop (SP)

Any technology, including IVR, ANI, or CTI, that presents corresponding data on the computer screen simultaneously with the incoming call.

Interactive Voice Response (IVR)

Also known as ‘Voice Response Unit (VRU)’ is a technology that allows customers to respond to a menu of choices (spoken by an electronic voice) by pressing the appropriate buttons on the telephone keypad or using voice (speech recognition).

Dual Tone Multi-Frequency (DTMF)

Also known as touch-tone is the signal to the phone company that you generate when you press an ordinary telephone keypad.

Contact Center As A Service (CCAAS)

A cloud deployed contact center that enables an organization to reduce capital expenditure and operate a fully featured, multi-channel contact center with greater scalability and flexibility.

Call Recording (CR)

Also known as ‘call logging’ is a technology that enables call centers to capture and record the interactions between the agent and the caller. The caller has to be informed before the call is recorded.

Automated Speech Recognition (ASR)

A solution to automate some or all parts of a customer call. It allows the caller to interact with the call center, using their natural language, without the aid of an agent.

Intelligent Call Router (ICR)

Is a telecommunications network service that is able to provide information on call queuing and agent’s availability across the call center’s network. It then directs the call to the most appropriate agent. It effectively has a similar job to a switchboard operator.


Is a software application used to automate the process of dialing to external phone numbers automatically.

Automatic Call Distributor (ACD)

A specialized software platform designed for handling many incoming calls. Based on the routing instructions, the system will direct the call to the most suitable skilled agent. It also queues calls.

User Interface (UI)

Is a broad term for any system, either physical or software based, that allows a user to connect to a given technology. Graphical user interface (gui) is a type of user interface that allows a user to interact with electronic devices through graphical icons and visual indicators.

Service Level Agreement (SLA)

Is a contract between the service provider and its customer that documents what services the provider will furnish and defines the performance standards the provider is obligated to meet.

Cross Selling (CS)

The practice of selling an additional product or service to an existing customer.

Customer Satisfaction (CSAT)

A metric that applies to all aspects of your business and gives you a deep insight as to how your business is perceived by your customers.

Expected Wait Time (EWT)

Refers to the expected time customers may be made to wait before they are able to speak to an agent.

Recorded Announcement (RAN)

An option of the Northern telephone system, which plays a recorded announcement for callers waiting for an available agent.

Full Time Call Recording (FTR)

Full time recording is when you record all of the calls, all of the time. FTR can be set on a per channel basis when Voxida is deployed in your call center.

Unified Communication (UC)

Is a set of communication services and solutions bundled, sold and delivered together as a single cohesive solution. UCS enables the use of voice, data, internet, video and other communication services through an integrated product or system which is developed by a single vendor or in collaboration with supported partners.

Skill Based Routing (SBR)

A method of routing calls in which the call is routed to the person best able to meet that caller’s needs, rather than simply routing to the first available or longest idle agent.

Response Time (RT)

The total amount of time it takes to respond to a service.

Nuisance Call (NC)

Refers to any type of unwanted, unsolicited telephone call. This includes prank/crank calls, telemarketing, and silent calls. Silent calls are telephone calls generated by the predictive dialer but there is no agent available immediately to take the call.

Call Avoidance (CA)

A proactive strategy implemented to reduce inbound call volumes to the contact center.

Automatic Number Identification (ANI)

Also known as ‘Calling Line Identity (CLI)’ is a feature on the telephone where you can see who is calling you before you answer.

Forecasting Accuracy(FA)

This refers to the percentage by which the inbound customer contacts that were forecasted for a particular time period varied from the number of contacts who actually contacted the center. In simple terms, forecasting accuracy refers to the difference between forecasted contact load and actual contact load.

Automatic Call Back (ACB)

A calling feature that allows the caller to hang up when the called individual is unavailable and instruct the system to call when the line is available or the called number is no longer busy.

Rostered Staff Factor (RSF)

Also known as Overlay, Shrink Factor or Shrinkage, RSF is a numerical factor that signifies the minimum staff needed over and above the base staff to achieve your required service level and response time objectives

Transferred Internal DN Calls (IDN)

The Transferred IDN number is the sum of all the calls the agent Transferred or Conferenced while on an active Non-ACD call. The number increases when the Transfer or Conference is complete.

Hold Direct Call Processing Time (HDCP)

The time (in seconds) that each agent spent with an ACD call placed on Hold. Hold time is measured from the time the agent puts the ACD call on Hold to the time the agent becomes active on the call again or the caller abandons the call.

Centum Call Seconds (CCS)

100 call seconds, a unit of telephone traffic measurement. The first C is the Roman numeral for 100. 1 hour = 1 Erlang = 60 minutes = 36 CCS.

Average Hold Time (HDCP time)

The average amounts of time per Answered ACD call that an agent (or agents) placed an ACD call on hold. Handling time is measured from the time the agent puts the ACD call on Hold to the time the agent becomes active on the call again or the caller abandons the call.

Automatic Call Distributor (ACDRB) Report Buffer

A component of ACD Performance Reporting that transfers your call center data from the Call Accounting Buffer to the ACD Parser program for processing into your historical database. The ACD Report Buffer is a software application that runs on a computer connected to the Call Accounting Buffer.

Average Number of Replies per Request (ANRPR)

The average number of replies tells you how many replies it takes to resolve a customer request.

Average Reply Time (ART)

With average reply time you’re measuring how long it takes your customer service team to reply to each message.

Average Time to Resolution (ATR)

To measure the efficiency of your customer service efforts, you’ll want to take a look at average time to resolution. This metric tells you how long it takes your team to resolve issues.


An electronic display showing; team performance, key performance criteria, service level, call queuing, etc within a call center. It can be used as a way of motivating the team, or as a reminder of the speed and level of service that the agents should be delivering.

Key Performance Indicators (KPI)

A set of measures used by a call center to measure performance/productivity.

Call Handling Analysis (CHA)

This is an approach to monitor the effectiveness and quality of handling of calls by the agents.

Blocked Call (BC)

A call that cannot be completed because of a busy condition.

Average Talk Time (ATT)

Measures the time an agent spends while speaking to a customer. This does not include the time a customer spends on hold or the time an agent does any work during or after the call.

Average Handle Time (AHT)

The amount of time an agent is occupied with an incoming contact. This is the sum of transaction time and wrap-up time.

After Call Work (ACW)

Also known as ‘wrap up time’ is the period of time immediately after the transaction with the customer is completed. Work could be keying activity codes, updating the database, filling out forms, or placing an outbound contact.

Key Performance Indicators (KPI)

A set of measures used by a call center to measure performance/productivity.

Abandoned Calls (CDNs)

The number of calls accepted into the CDN, but abandoned before being answered through the controlled operation or routed according to the CDN's script.

Voice of the Customer (VOC)

A term used in business and Information Technology (through ITIL) to describe the in-depth process of capturing a customer's expectations, preferences, and aversions.

Telephone Service Factor (TSF)

Measures how quickly incoming calls are answered. The customer specifies the time (in seconds) in the programming of the telephone system.


An agent is considered Manned if they are logged into the telephone system and able to take ACD or Non-ACD calls. When Manned, agents can be in the Available, Not Ready, ACD, or Non-ACD states.

Live Monitor (LM)

Live Monitoring is the activity of "listening in" to a call in progress, independently of the recording process. Live Monitoring is useful for real-time quality assurance or to be able to determine when to record a conversation.

Universal Agent (UA)

An agent who can handle multiple types of contact.

Talk Time (TT)

The time elapsed from when an agent answers the call till the agent disconnects the call.

Outbound Call (OC)

Calls that are initiated by a call center agent to a customer and are different from calls that come into the call center and are answered by the agent (inbound call).

Next Available Agent (NAA)

A call distribution method where the first contact in the queue is routed to the first available agent. If no queue exists, contacts are routed to the agent who has been sitting idle for a long time (longest available agent).

Multi-Skilled Agent (MSA)

Agents who have the skills to handle a variety of calls.

Blended Agent (BA)

An agent who is trained to handle both and outbound calls and related applications as needed.

Agent Status (AS)

Current work mode of the agent. This can be busy on call, available to receive calls, unavailable to receive calls, and after call work mode.

First Call Resolution (FCR)

One of the most important call center metrics. This is focused on resolving a customer’s query or complaint on the first call. FCR is used for monitoring the quality of service customers receive by counting the number of times their issues got resolved on their first point of contact.


Responsible for handling incoming and outgoing calls, an agent is the one who is known by names like customer service representative (CSR), telephone sales or service representative (TSR), associate, consultant, engineer, operator, technician, account executive, team member, customer service professional, staff member, attendant and specialist.

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