What is Call Center?“A place where calls are made and received.”
The objective of this workshop is to provide an introduction to call center operations and the role of WFM in running a typical call center
Type of Call Centers
1. Inbound – HDFC Bank Customer Service
2. Outbound – Car or Bike helpline Telesales
3. Blended – Incoming calls with Outbound calls or emails or Web chat
Geographic Scope1. Internal – serves only internal customers, internal Transport
helpdesk
2. Local- Serve customers in limited geographic for example local taxi or bus service
3. Regional-Services beyond local but limited by region for example Videocon/Aircel Mobile Companies
4. National-Take calls from all states for example Indian Railways
5. International- Take calls that extend beyond national boundaries
Financial Structure
1.Profit Center :- • Call center that generate revenue for example Indian
Railways Reservation center
2.Cost Center:-• Call center that generate no direct revenue
CALL LIFE CYCLE FROM CUSTOMER TO AGENT
Customer
1800-969-4545
• PSTN : public switched telephone network• PBX : Public Branch Exchange • CTI : Computer Telephony Integration• CMS : Call Management System • TTS : Text To Speech • IVR : Interactive voice Response
PSTN
KT
▷ Echo (Order System)
CTI CMS RecordingPBXAuto
ordering TTS
Local Network (LAN)1800-414-4545………
Order/SR
1800-266-4545
Call Master
Agent
Call Line Quan-tity
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Work force planning (WFM)
“Right number of people, at the right time to take right number of volume”.
1. Forecasting2. Scheduling3. SD4. MIS
FORECASTING:
The process of predicting future values using the current or historical information on causes, customer behavior or performance
"It is tough to make predictions, especially about the future.“
FORECASTING-A BLEND OF ART & SCIENCE
Art– Predicting the future– The Human Factor
– Intuition– Instinct– Judgement
Science Uses tools Pencil, paper Calculator Statistical techniques Spreadsheet software Forecasting software
FORECASTING HORIZON
• Long-range (more than 12 months ahead):– Used to plan contact center capacity
• Intermediate-range (3 to 12 months ahead):– Used to plan workforce levels, allocate funds
among divisions, and develop training schedules• Short-range (1 to 12 weeks):
– Used to schedule workforce, intra-day forecasting and re-forecasting
FORECASTING METHODS• Judgmental methods
– Expert opinion– Market surveys/tests– Delphi
• Statistical methods– Point estimate– Simple average– Simple moving average– Weighted average– Weighted moving average– Time series models– Regression (or causal) models
• Combination method– Statistical forecasting with judgmental adjustments
Judgmental methods– Expert opinion– Market surveys/tests– Delphi
FORECASTING METHODS
Expert Opinion:
Gathers judgments and opinions of key personnel based on their experience and knowledge
– Workforce managers are a good source for the initial volume forecasts for new services and special events with no past history
Market Surveys/Testing:
Utilizes questionnaires, telephone contacts, field tests, or personal interviews
– Testing the new billing statement format with a select group of customers to determine its impact on call volumes and AHT
Delphi:
Experts are individually questioned about their opinion of future contact volumes and AHT.
• Their responses are summarized by an outside party and returned to the experts until a consensus is reached by the group.
FORECASTING METHODS
• Statistical methods– Point estimate– Simple average– Simple moving average– Weighted average– Weighted moving average– Time series models– Regression (or causal) models
POINT ESTIMATE
Takes data from a point in the past, assumes the next point will be the same. For example Weather Prediction of the high temperature for June 1st of coming year could be derived by simply using number from last June1st.
Shortcomings Doesn’t account for long-term change Cannot determine whether original data was typical
or unusual Doesn’t recognize recent trends
SIMPLE AVERAGE
Sum all data points and divide by the number of data points used
Shortcomings• Weighs all events equally• Every day likely to be like any other day• No underlying changes• Assumes data consistent across time
SIMPLE MOVING AVERAGEMoving average is one where old data is dropped out as new information is added. For example if June 1st Temperature is 95 degrees, then oldest piece of information(83 degrees in 1990)
Shortcomings• Uses only a fixed span of data• Significance of recent trends is over emphasized
WEIGHTED AVERAGE
Emphasizes the most recent events and recognizes something has fundamentally changed
• Assumes:– Today better predictor of tomorrow than past data– More weight should be given to recent data
• Best for call centers with unpredictable fluctuations• Accounts for fundamental shifts in underlying call
patterns
WEIGHTED MOVING AVERAGE
Combines the moving average and weighted average methods• New data is continually averaged in with old and
weighted more heavily• Older values are retained• Statistical value of sample improves over time• Used by most workforce management tools
TREND AND SEASONALITY
• Trend is the long-term change in call volume expressed as the average monthly increase or decrease.
• Seasonality is the month to month fluctuation in call volume that can be expected to recur each year.
PRINCIPLES OF TREND AND SEASONALITY
Call volume is influenced over timeTrend and seasonality are the influencesCalculating these influences is a 2-step process
Calculate trendDetrend--bring old data up to the current point
CALCULATING TREND
Preferably with 24 months of data, calculate annual % change in actual call volume for each month from year to year:((Year B - Year A) / Year A) * 100 = % of change
Calculate the simple average of each month’s percent of change
To convert to monthly trend rate, sum each month’s percent of change, divide by number of months of data used
Monthly Call Volume Forecast
Monthly Call Volume
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REGRESSION ANALYSIS
Where volume is dependent upon an event or variable. For example if HS18 advertise their product on a newspaper and has kept
records of catalogs mailed and corresponding number of incoming calls.
Month Call Volume Number of CatalogsSep 72000 123000Oct 85000 135000Nov 92000 140000Dec 101000 155000Jan 54000 86000Feb 55000 76000Mar 76000 94000Apr 102000 164000May 81000 128000Jun 86000 131000
According to the Table greater the number of catalogs shipped, the greater the calls received.
The data collection process Data Validation Dealing with Aberrations Impact of sample sizes Sources of call data Business drivers & factors Simple, Moving & weighted averages Time Series Analysis Calculating Trend Identifying seasonal Patterns Calculating day of week factors Identifying time of day patterns The impact of special events Shortcut Forecasting approaches Calculation & Formula Review
Combination method
DATA COLLECTION PROCESS
•The most reliable data source is Avaya or any Platform Call Center is working on.•The data has to be collected on split skill basis & not on any other parameter.
DATA VALIDATION-1
Validating of data is CRITICALMust use normalized data, adjusted for aberrationsAberrations
Some “normal” or “repeatable”
DATA VALIDATION-2How much data do I need to start?Suggested sample sizes:
To determine seasonal patterns and annual growth rate: 2 yearsTo determine day of week patterns: 4-6 weeksTo determine hour of day patterns: 4-6 weeks of hourly data
Brand New Call Center?Marketing StudiesBenchmarking StudiesClientLogic dataClient DataOthers are “special”,Store aberrant data as future predictorAlways note on reports whether electronic or paperLong distance carrier, Genesys,Computer Telephony IntegrationAgent hash marks, Marketing projectionsTools range from manual to automaticACD reports,Telephone company
DATA LIMITATIONS
Technology: (Variations among ACDs)Types of dataDifferent technologyDifferent features
Call routing influences reportingDefault Queues Transfer calls Overflow callsSkill-based routing
CONSIDER RANDOM VARIATIONS
Past events may be used to forecastIdentify predictable variations
Capture aberrationsIdentify Unpredictable Variations
One time eventsActs of nature, etcMay not know when it will happen again, but will know
what it will look like
CALCULATING DAY OF WEEK PATTERNS
• Daily Call Volume Estimate:• Choose several recent “clear” weeks• Calculate average daily total and weekly total• Calculate day of week %’s for each day of week• Expected percentage is derived from past and
applied to future• Account for specific call center fluctuations
based on the nature of the business
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INTRA DAY VOLUME PATTERN
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CHECKING THE STATIONARITY - REMOVE TREND
Differencing: Method of removing upward / downward trend in a data series. After the data has no trend, the data becomes STATIONARY.
Microsoft Excel Worksheet
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Adjusting special days
Take the weekly data for 6 weeks prior to the special week.Calculate the median of first 3 weeks and the last 3 weeks. Average the two medians. Calculate the growth rate of volume in special week over this
average. Average the Growth rates.If the average GR falls between +/- 10%, call it normal or
else special. Inflate / deflate the special days with these factors and get
the final daily numbers.
REMOVE SEASONALITY
Estimating the Seasonal Index / Seasonal Dummies:
Microsoft Excel Worksheet
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SEASONALITY
Seasonality is the normal fluctuations experienced in the same months from year to year. Different depending on your business.
Once trend is identified, it is removed as factor; what’s left is the effect of seasonality.
“Detrending” Is the process of removing trend from the data.
TIME SERIES MODEL
A time series is a set of observations measured at successive points in time
TIME SERIES MODELS
Time series models analyze historical data to determine patterns and dependencies for forecasting future values• Patterns
– Trend– Seasonal
• Correlation and dependencies between two or more time series
TIME SERIES - TREND
• Trend– A time series with trend gradually shifts to
relatively higher or lower values over a period of time
LINEAR OR NON-LINEAR REGRESSION
Trend may be– Increasing, decreasing or non-existent– Linear or non-linear
SEASONALITY
• A regular pattern of variability in time series data that repeats over a year or shorter periods
TIME SERIES - PATTERNSSeasonality in contact volumes and AHT. Intra-day. Daily. Monthly. Quarterly. Annual
CORRELATION COEFFICIENTCorrelation between two time series is a measure of dependence scaled to [-1, 1]
For two positively correlated time series, if the value of one is .high. in one period, the other is likely to be “high” also
For two negatively correlated time series, if the value of one is .high. in one period, the other is likely to be “low”
DEPENDENCIES BETWEEN VOLUMES, AHT AND INDICATOR VARIABLES
EXCEL CORREL FUNTION - CORRELATION COEFFICIENT FOR TWO TIME SERIES
Correlation between two time series is a relative measure of dependency. Values closer to 1 or -1 represent strong relationshipsCoefficient is also know as relative standard deviation (RSD)
SIMPLE DAILY MOVING AVERAGES
DAY OF WEEK AND MEAN DAY OF WEEK FACTORS
WEIGHTED MOVING AVERAGESWeighted (e.g. percentages) Moving AveragesAssigns higher weights to some actual values (usually the most recent ones) than the others
DAY OF WEEK FACTORS WITH THE WEIGHTED MOVING AVERAGES METHOD
INCLUDING WEEKLY GROWTH FACTORS WITH THE WEIGHTED MOVING AVERAGES METHOD
INTERVAL FORECASTS
Interval level forecasts are generated from daily forecasts using the interval factors (%) calculated by applying the same approach used to compute the day of week factors
TIME SERIES MODEL COMPONENTS
Special Events
. Known calendar events such as July 4th (US Independence day), 1st day of a month. Planned events such as campaigns, mailings. Unknown events such as computer viruses, storms
SPECIAL EVENTS
SPECIAL EVENT DAY FORECASTINGForecasting with special eventsStep 1: Identify special event days in the past and over theforecast horizon
Step 2: Regular day forecasting. Forecast contact volume and AHT for the past special event days. Replace the past special event day actuals with the forecasted values. Forecast future contact volumes and AHT values over the forecastinghorizon
Step 3: Special event day forecasting. Forecast future contact volumes and AHT for the special event daysover the horizon using past special event day actuals. Replace the base forecasts found in Step 2 with the special event dayforecasts from this step
TIME SERIES MODELS - OUTLIERS
An outlier is an actual that issubstantially higher or lower than theactuals observed in the similar periods
. Outliers are caused by one-time or recurringunpredictable events. Events causing an outlier may be known(e.g. web site problems increasing call volumes due to civil aggitation)or unknown
OUTLIERS
Outliers should be excludedin forecasting to improve forecast accuracyby replacing them with forecasted values
OUTLIERIf not detected and replaced, outlier andmissing values will affect your forecasts andaccuracy negatively
ConclusionCall centers with good forecasts do not necessarily have inherently stable environments. Rather, they have established good ties with other departments, pulled in the data required, and established a forecasting process they are continually working to improve.
They recognize that the responsibility for producing a good workload forecast cannot rest solely on the person or group who "does" the forecasting. Instead, they view forecasting as a call center-wide process and work on all contributing factors.
WFM-SCHEDULING
WHAT IS CALL CENTER SCHEDULING?
Scheduling right number of people at the right time, to take right number of calls, to maximized the sales and customer satisfaction.
SCOPE OF CALL CENTER SCHEDULINGScheduling scope includes creating/generate staffing schedules that optimize a wide range of factors :-
• Agent availability• Work rules• Skills• Holidays• Breaks• Service levels• Center budgets
How do you SCHEDULE• Hour of operations
• 24 hrs • 12 hrs• 8 hrs
• SLA Target ASA (Average Speed of Ans 30 Sec)• 80/20• 90/20• 95/30• 99/30
• Type of Scheduling• European (49% - 56% ASH)• North America (30% - 35% ASH)• Indian (20% to 28% ASH)
• Week Off/Day off preference• Create fine balance between volume forecast & Agent Week off preferance• Needs to maintain fairness tracker so that everyone get equal Week Off
preference• Agent’s Week Off preference request for Week• Scheduling Lunch and Break so that Ans capacity doesn’t impact overall SLA
How do you SCHEDULE• Call Volume Trending
• Day of the week factor, when volume is less give more week-off
• Staffing based on Skill priority and Que priority
SCHEDULE after-effectsOhh good !!!!
I got what I asked for
Why I am not getting week Off on Sunday
for last 4 weeks
Nooo.. Why my planned leaves are not reflecting
If you are not getting what you want it can be because of• Your Skill Priority• Your Que Priority• Call Volume for that week• Any special marketing campaign• Festival session and everyone is asking for leaves
How do you SCHEDULEScheduling is needed to answer below mentioned questions
• Achieving Performance Target/Quality of Service Target• ASA (Average Speed of Ans 30 Sec)
• Week Off/Day off• Create fine balance between volume forecast & Agent Week off
preferance• Needs to maintain fairness tracker so that everyone get equal Week
Off preferance• Agent’s Week Off preference request for Week• Scheduling Lunch and Break so that Ans capacity doesn’t impact
overall SLA
• Hours of operations• 24 hrs • 12 hrs• 8 hrs• Call Volume Trending
• Including agent availability• Work rules• Skills• Holidays• Breaks• Service levels• Center budgets
Thank you
WHAT IS THE IMPACT OF ONE AGENT?• 175 calls per half-hour, 5 minute AHT (280 talk/20 acw)
• (29.2 erlangs)
Number of Staff
Average Speed of Answer
Service Level (in
30 sec)30 298 sec 24%31 107 sec 46%32 54 sec 62%33 30 sec 74%34 18 sec 82%35 11 sec 88%
Staff Occupanc
y.97.94.91.88.86.83
6 am 10 pm
Peo
ple
Think of your shifts as LEGO building blocks. The more sizes and types of blocks, the better you can build your model.
SCHEDULE INFLEXIBILITY
WHAT IF CALLS TAKE 30 SECONDS LONGER TO HANDLE?
Forecast versus Actual
Time of Day
Forecast Calls
Forecast AHT
Forecast Staff
Actual Calls
Actual AHT
New Staff
Net Staff
6:00 280 320 56 280 350 61 - 5
6:30 310 320 62 310 350 68 - 6
7:00 350 320 69 350 350 76 - 7
7:30 380 320 75 380 350 82 - 7
8:00 420 320 82 420 350 90 - 8
8:30 450 320 88 450 350 96 - 8
WHAT IF VOLUME IS 10% BELOW FORECAST?
Forecast versus Actual
Time of Day
Forecast Calls
Forecast AHT
Forecast Staff
Actual Calls
Actual AHT
New Staff
Net Staff
6:00 280 320 56 252 320 51 + 5
6:30 310 320 62 279 320 56 + 6
7:00 350 320 69 315 320 63 + 6
7:30 380 320 75 342 320 68 + 7
8:00 420 320 82 378 320 75 + 7
8:30 450 320 88 405 320 80 + 8
6 am 10 pm
Peo
ple
The Result: A better fit with less understaffing and
overstaffing
OPTIMIZED SCHEDULE
REPORTING SERVICE LEVEL• Activity
• An executive calls and wants to know how service level looked yesterday.
• Your service level goal is 80% in 20 sec.
• Questions:Did you meet your goal?Why or why not?What are the possibilities for reporting the numbers?Which method do you think is best?
PAYBACK EXAMPLE Real-Time Adherence Monitoring
Number of Agents
@ $15/hour wage rate
@$20/hour wage rate
100 Rs 32,500 $ 43,333
250 $ 81,250 $108,062
500 $162,500 $ 216,125
1000 $325,000 $ 432,250
Assumption: 5 minutes savings per agent per day