Analysis of the Manzana

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  • THE UNIVERSITY OF NEW SOUTH WALES

    School of Mechanical and Manufacturing Engineering

    Semester 1, 2013

    GSOE9810 Process and Product Quality in Engineering

    Assignment 1: Case Study

    Manzana Insurance: Fruitvale Branch (Abridged)

    Group Number: 13

    Team Members:

    Last Name First Name Student ID AKOMEAH Matilda 3447443

    BASSAN Marco 3451903 HE Jie 3469345

    KASIM Michael 3285455 OROMIEHIE Ebrahim 3314896

    ZHANG Yan 3352792

    Lecturer In-charge: Dr Eric van Voorthuysen

    Tutor In-charge: Mr James Baulch

  • 2

    1. Process Flow Diagram The Process Flow Diagram, or PFD, of Manzanas Fruitvale branch is shown in figure

    1. Some important features of the PFD are as follow:

    The coloured arrow is used in order to differentiate the origin of insurance

    request. As shown in the diagram, the RUN, RAIN and RAP are originated

    from the customer. On the other hand, the RERUN is originated from the

    branch record.

    The black arrow explains the path that each policy undergoes before being

    delivered to branch record, customer and agent.

    Automatic Renewal System represents the current computerised system to

    produce RERUN request.

    The Branch Record is assumed to store both hard copy and soft copy of the

    policy, and the data is used as the input for Automatic Renewal System.

    The elements involved in the PFD are used base on the general convention of process

    flow diagram, which is discussed by Foster, 2013.

  • 3

    Figure 1 PFD of Fruitvale branch

  • 4

    2. Performance of Manzanas Fruitvale Branch The assessment of the branch performance is conduced based on two key measures.

    These two key measures are financial and operational performance.

    2.1. Financial Performance The data used in analysing the financial performance is taken from the Financial

    Summary, Fruitvale Branch in Exhibit 5 of the case study. The key concept in

    analysing this performance is based on the ability of the branch to achieve satisfactory

    results or positive trend on some important economic data. The failure of meeting

    these criteria indicates the existence of problems, or issues, that can be verified based

    on the operational performance.

    2.1.1. Branch Profit

    The profit is an accounting measure, and the value is obtained by subtracting revenue

    with expenses (Sullivan, 2012). In general, the revenue of a healthy company is more

    than the expenses, and therefore profit is generated, otherwise there will be financial

    losses. = [1]

    The profit of the branch is shown in the following figure.

    Figure 2 Branch profit

    y = -244.21x + 2257.7

    R = 0.94586

    -500 0 500 1000

    1500 2000 2500

    Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 1989 1990 1991

    Pro$it in

    Tho

    usan

    d ($)

    Year

    BRANCH PROFIT

  • 5

    Some key points based on figure 2 are as follow.

    The trend of the profit is assumed to follow linear regression.

    The reliability of the trend line is assessed based on the R-Squared value. A

    reliable trendline commonly has R-Squared value of 1 or near 1 (Microsoft,

    2013). The R-Squared value of the profit trendline is 0.94586, thus the

    trendline is reliable.

    The slope of the trendline is -244.21, thus the profit has a negative trend.

    There are two significant financial losses in the last two quarters.

    The negative trend and losses are mainly due to the gradual drop of revenue and not

    because of increase in operating expenses. The operating expenses increased by

    approximately 16.31% from the first quarter of 1989 to the first quarter of 1991,

    mainly due to Finance Charge and introduction Salary/Plus program. This increase is

    less significant in compare to the significant drop of gross underwriting result of

    approximately 56%. The computation is summarised in the following table.

    Financial

    Data

    Q1 1989

    (A)

    Q1 1991

    (B)

    Difference

    (B-A)

    Increase or

    Decrease (%)

    Operating

    Expenses 1238 1443 205 16.56%

    Gross

    Underwriting

    Result

    3003 1322 -1681 -55.98%

    Table 1 Revenue and expenses data

    Furthermore, the significant elements that construct the gross underwriting result are

    the net underwriting revenue and the ordinary losses. As can be seen in figure 3

    below, there is minimum variation of net underwriting revenue throughout the period,

    while the ordinary insured losses has been drastically grown over the period.

  • 6

    Figure 3 Gross underwriting results analysis

    2.1.2. Market Share

    The drastic growth of ordinary insured loss shows contradiction between market share

    and amount paid to the customer in term of ordinary insured loss. The amount of

    ordinary insured loss is commonly increased if the market share is increased as well,

    or there is a positive correlation. In the case of Fruitvale branch, the ordinary

    insurance loss increased, but the market share decreased due to high renewal loss.

    This issue can be addressed by analysing the ratio between ordinary insured loss and

    the total policy. The analysis is summarised in the following figure.

    Figure 4 Ratio between ordinary insured losses and total policies

    0 2000 4000 6000 8000 10000

    Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 1989 1990 1991

    $ Va

    lue (in Th

    ousand

    )

    Year

    GROSS UNDERWRITING RESULTS ANALYSIS

    Gross Underwriting Results Ordinary Insured Losses Net Underwriting Revenue

    0.00 2.00 4.00 6.00 8.00 10.00

    Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 1989 1990 1991

    Ratio

    Year

    Ordinary Losses/Total Policies

  • 7

    The increasing ratio in figure 4 indicates the existence of problem in regard to the

    quality of the customer, performance of the agent and the companys underwriting

    standard. These issues will be addressed in the later section of this assignment.

    2.1.2. Renewal Loss

    The lack of ability of the company to maintain their existing customer is represented by the

    high renewal loss. The renewal loss has a significant impact toward the profitability of the

    branch. The revenue generated by the renewals is shown in the figure 5 below. The revenue

    generated by the renewal starts to decrease from the first quarter 1990, and it cancels out the

    revenue generated by the new policies. Thus, it has a direct effect toward the profitability of

    the branch.

    Figure 5 Renewal (Dollar Value)

    2.2. Operational Performance The operational performance of the branch is assessed based on three main measures.

    These measures include customer satisfaction level, employee attitudes toward

    companys strategy and day-to-day operation performance.

    2.2.1. Customer Satisfaction

    The performance measures in regard to customer satisfaction in this case study are the

    turnaround time, late number and renewal loss rate.

    6100 6300 6500 6700 6900 7100 7300

    Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 1989 1990 1991

    $ Va

    lue (in thou

    sand

    )

    Year

    Renewal

  • 8

    Turnaround Time (TAT)

    As indicated in the case study, the TAT has increased from three days to more than

    five days. This is a significant competitive disadvantage for Fruitvale branch knowing

    that agents typically send their clients to the company with the shortest TAT, mainly

    due to the opportunity for obtaining commission earlier or selling more policies. It is

    clear that in the insurance industry the TAT is a key item. The situation is worsens

    due to the fact that Golden Gate, Manzanas main competitors, has decided to

    implement a guaranteed TAT of one day. Thus, a significant change toward

    improvement of TAT is necessary if Manzana want to stay competitive in the

    business.

    Late Number

    Pareto Analysis is conducted in order to justify that the RERUN has the most

    significant affect toward the total late figure. The data for the analysis is taken from

    Exhibit 6, and the result is shown in the figure 6 below. The result shows that RERUN

    contributes to more than 80% of the total late figure. The high late figure on the

    RERUN indicates poor service toward the current customer, and thus it lead to poor

    customer satisfaction level.

    Figure 6 Pareto analysis in late policy

    Furthermore, the reason behind the high renewal late is due to the priority that is

    given to new policy. The summary in Exhibit 6 shows that the late figure of RUN and

    RAP is zero, while RAIN and RERUN increase throughout the year. This issue is

    strongly related to the profit generated by new policy and the employee attitude

    99.60 99.70 99.80 99.90 100.00

    0 500 1000 1500 2000 2500 3000

    RERUN RAIN RUN RAP Percentage (%

    )

    Num

    ber of Late

    Type of Policy

    Pareto Analysis on Late Policy

    Frequency Cummulative Frequency

  • 9

    toward the implementation of Salary/Plus system, which will be discussed in detail in

    the later section of this assignment.

    Renewal Loss Rate

    The high number of renewal late leads to high renewal loss rate. As shown in the case

    study, the renewal loss rate increased from 33% in the second quarter of 1990 to 47%

    in the second quarter of 1991. On the other hand, the renewal loss rate of Golden

    Gate, Manzanas main competitor, is 15%. Although renewals do not generate high

    profit for the company, losing some market share each year is a major problem.

    The lost of market share can be measured quantitatively by analysing the renewal rate

    figure, which is derived from the data given in Exhibit 7. In 1989, renewal rate was

    85.9% and it decreases to 69.2% in 1991. The computation is summarised in the

    following table.

    Request Summary 1989 1990 1991 (6 months)

    RERUNs 5166 4987 2081

    Renewal Lost 849 1717 926

    Total 6015 6704 3007

    Renewal Rate (%) 85.89% 74.39% 69.21%

    Table 2 Summary of renewal rate

    2.2.2. Inconsistency in Following Company Policy

    The company has used first-in-first-out (FIFO) system as a policy for considering

    requests. However, this policy is not support by employees. As mentioned before, the

    employees tend to give priority to new policy. The discussion of the violation of

    company policy, which includes the cause and the affect, will be included in the next

    section of this assignment.

    2.2.3. Uncontrolled Day-to-Day Operation

    The data on policy processing time in Exhibit 4 shows that there is a lack of

    standardisation in performing a task. This issue is justified based on the high number

    of standard deviation, which mean there is a significant variation in performing a task.

    The worse case scenario is taken from the processing of RERUN in the underwriting

    department. The mean in performing the tasks is 18.7, while the standard deviation is

  • 10

    19.8. This issue will be further analysed in detail in the next section by using the

    statistical concepts known as coefficient of variation.

    2.3. Outcome The outcome of this analysis is that the branch performance is poor in term of both

    financial and operational. In term of financial performance, the branch profit has a

    negative trend and there is a significant loss in the last two quarters. Next in term of

    operational performance, the ineffective day-to-day operation and poor attitude of

    employee toward company policy adversely affects the customer satisfaction level.

    The TAT has increased recently, and the renewal late and loss rate also increase

    recently which indicates poor customer satisfaction and lost of market share.

  • 11

    3. Issue Analysis This section focuses on the issues that have been addressed in the previous section as

    well as the causes of these issues. The following figure summarised the issue analysis

    of the Fruitvale branch.

    Figure 7 Issue tree

  • 12

    3.1. Relationship Among Problems

    3.1.1. TAT and Renewals

    The main relation of TAT toward renewal late and loss are mainly the use of TAT to

    set the due date of new policy. The new policy is currently prioritised in different

    department, thus the renewal process will be further delayed. This delay will increase

    the renewal late, in which turns out to be renewal loss.

    3.1.2. TAT and Profit

    The main relation of TAT and profit is that the agents use TAT as the main criteria to

    measure the branchs capability. The high TAT leads to competitive disadvantages,

    thus it will be less attractive to the agents. Furthermore, it will lead to lower incoming

    customer, thus lowering the profitability of the company.

    3.2. The Causes of High TAT

    3.2.1. Inconsistent Implementation of Operational Strategy

    The original operational policy in each stage of the underwriting process is First-In-

    First-Out (FIFO) system in which orders are processed in the same order in which

    they arrive (Mieghem, 2005) . The FIFO system in Manzanas operational context can

    be defined as the documents, or requests, are processed in order of their arrival,

    regardless of the importance and the complexity of the requests. However, the

    implementation of this policy is considered to be ineffective. The ineffective

    implementation of FIFO system is caused by the lack of supervision, the shortage of

    leadership and authority as well as the implementation of Salary/Plus system.

    The manger of each department shows a negative attitude toward correct

    implementation of FIFO policy. The manager in the underwriting department prefers

    to prioritise RUN and RAP due to its profitability, while the manager of the policy

    writing prefers to priorities simple task for the purpose of reducing the backlog.

    Furthermore, the lack of authority and leadership is shown in the attitude of manager

    of rating department. The manager recognise the issue and the affect of violating the

    FIFO policy, but the manager could not fix the problem due to the order given by the

    higher management.

  • 13

    The second cause of violation of FIFO policy is the company's strategy of giving

    incentive for each new policy completed and such incentive was not applied for the

    renewals. This quantitative performance measure leads to prioritisation of request,

    thus the FIFO policy is violated. Furthermore, the main outcome of this issue is the

    non-value added activity, which is sorting the document by priority. This activity

    leads to high backlog number, which adversely affect the computation of TAT.

    3.2.2. Poor Resource Scheduling and Allocation

    The poor resource scheduling is justified based on the unbalance workload throughout

    the period, and it results in either overtime or idle period. Next, the poor resource

    allocation can be analysed based on the utilisation rate in each department. The

    computation summary of the utilisation rate is shown in the following table. The

    utilisation rate shows that the rating and policy-writing department are overstaffed,

    which result in low utilisation rate.

    Table 3 Utilisation rate

    The significant cause of this problem is the outdated data of processing time required.

    The inaccurate data leads inaccurate estimation of the resource and time required to

    complete the job. Further, the affect of poor resource allocation and scheduling is

    mainly due to the backlog that it creates. The large number of backlog affects the

    computation of TAT.

    3.2.3. Unstandardized Working Procedure

    The data provided in Exhibit 4 shows that the 95% SCTs are derived based on the

    policy processing time, and inconsistent processing time will lead to inaccurate SCTs.

    Distribution Underwriting Rating Policy Writing

    Daily Activity 40 Requests 40 Requests 40Requests 40Requests

    Average Time

    Required 40min 30min 70min 55min

    Total Time Needed 26.7hours 20hours 46.7hours 27.5hours(75% of

    daily requests)

    Capacity Available 30hrs 22.5hrs 60hrs 37.5hrs

    Utilization rate 89% 89% 78% 73%

  • 14

    The inconsistent processing time is justified based on the high standard deviation

    values in some of the process stages. The selected quantitative analysis in order to

    provide an objective measure of the inconsistency is coefficient of variation.

    The coefficient of variation, or CV, is the relative dispersion, and it is computed as

    the percentage ratio of the standard deviation to the mean. The general interpretation

    of CV is that data with CV of 30% or more indicates lack of process control (Brown,

    1998). The mathematical equation for CV is as below. Next, the CV for policy

    processing time in each stage is calculated using the CV equation, and the result is

    summarised in table 4 below.

    % = 100%

    Coefficient of

    Variation

    Type of Policy

    RUNs RAPs RAINs RERUNs

    Distribution 44.8% 49.8% 21.1% 22.1%

    Underwriting 73.4% 64.5% 51.8% 105.9%

    Rating 27.2% 21.0% 24.3% 12.8%

    Policy Writing 14.5% - 15.9% 19.0%

    Table 4 Coefficient of Variation Result

    The computation shows that the process variation in Distribution and Underwriting

    department is mostly out of control with respect of 30% limit as specified by Brown,

    1998. The variation of rating department is relatively high, while the processing time

    in Policy Writing department is relatively in control.

    Furthermore, in relation to the computation of TAT, the uncontrolled process leads to

    high variation and SCT, and therefore the TAT will be overestimated. The

    introduction of standardised procedure may be able to provide better process control,

    and therefore the TAT will be more accurate. The relation is shown in Figure 1 below.

  • 15

    Figure 8 Relation between process control and TAT

    3.3. The Causes of High Renewal Late and Losses

    3.3.1. Unreasonable RERUN Processing and Due Date

    The renewal losses and late rate are related to unreasonable RERUNS processing and

    due date. A computer automatically generated a RERUN 30 days before the

    anniversary of the policy and the anniversary became the due date. However, the

    RERUNS will be released at the last day before the due date which leads to the

    congestion of RERUNS and less flexibility of process, and this will ultimately cause

    the high rate of renewal late and losses and long time TAT.

    3.4. The Causes of Negative Profit

    3.4.1. Poor Originating Agent Performance

    The number of new policy written and the ordinary insured losses are the two main

    parameters that can be used to measure the performance of originating agent. Based

    on the financial summary in Exhibit 5, the net underwriting revenue is relatively

    stable while the number of ordinary insured losses increases rapidly from $4,176,000

    in the first quarter of 1989 to $6,453,000 in the second quarter of 1991. The total

    number of policies is decreasing in this period so the rise of the ordinary insured

    losses can be explain with the selection of bad customers by the agent. In addition, the

    poor relationship and lack of communication between the branch and agents is one of

    the contributing factors of this issue. Thus, the agents might prefer other property-

    insured company due to lower TAT and result in a rapid increase of ordinary insured

    losses.

    3.4.2. Implementation of Incorrect Strategy

    The new management implement a new strategy in which the branch was divided into

    three territories based on the geographic position. The main purpose of this strategy is

  • 16

    to improve the responsiveness toward the agent. Nevertheless, from Exhibit 7, it is

    clearly shown that from 1989 to 1991, the number of lost renewals increased from

    849 to 1852 (two times of 926 in first 6 months in 1991) and the Gross premium was

    nearly constant during two years. As a result, it seems that the geographical

    restructuring is ineffectiveness and it has a significant impact to the companys

    profitability.

  • 17

    4. Problem in Turnaround Time (TAT) Calculation The Turnaround Time, or TAT, is defined as the number of days between the receipt

    of a new commercial policy, or RUN, and the issuance of a final policy. The

    calculation of TAT by Fruitvale branch is included on Exhibit 3. The context of this

    calculation is based on the ending week of September 6, 1991.

    There are some problems identified in regard to the current calculation of TAT. The

    following are a brief list of the identified problems:

    1. Obsolete input data from Exhibit 4

    2. Incorrect assumption of process start-up

    3. Incorrect assumption of requests transfer procedure

    4.1. Obsolete Data The TAT calculation in Exhibit 3 is taken from 1991 context, and it utilised the

    Standard Completion Time, or SCT that is constructed based on the policy processing

    time in 1986. These SCTs are considered to be obsolete due to the installation of

    computer system in Rating and Policy Writing Department during late 1980s and

    early 1990s. The installation of computer system has significantly reduced the

    processing time required to complete activities in these two departments. Therefore,

    the utilisation of the 95% SCTs of Rating and Policy Writing Department is not valid,

    and it leads to overestimation of TAT. Furthermore, the utilisation of the old data in

    the TAT calculation shows that the company does not have a clear strategy in

    managing their data.

    4.2. Inaccurate Assumption of Process Start-up The computation of TAT in Exhibit 3 is conducted based on the assumption that, the

    process in the next department can only start once the process in the previous

    department has been completed, regardless of the requests that are currently in the

    queue. For example, the requests in the Underwriting Departments (3 RUNs, 7 RAPs,

    6 RAINs and 36 RERUNs) cannot be processed until the requests in Distribution

    Department have been completed, or in other word the Underwriting Department

    needs to wait for approximately 0.6 days before they can start the process. The

    graphical representation of this issue is shown in figure 9 below.

  • 18

    Figure 9 Sequential process start-up assumption

    The assumption of the sequential process start-up leads to overestimation of TAT.

    The alternative assumption that can be used to estimate TAT is by assuming processes

    in a different department start in a parallel manner. It means that each department will

    immediately process requests that are currently in the queue and does not wait for the

    previous department to complete their tasks. This assumption will reduce the

    estimation of TAT as well as improving its accuracy. The graphical representation of

    this assumption is shown in the following figure.

    Figure 10 Parallel process start-up assumption

  • 19

    4.3. Incorrect Assumption on Requests Transfer Procedure The current computation of TAT assumes that the requests are transferred in batch.

    This assumption is incorrect since the company does not implement a batch transfer

    policy, and it also results in overestimation of TAT. Thus, the individual transfer is

    preferable and the use of this assumption may improve the reliability of TAT.

    Furthermore, the utilisation of individual transfer required addition delay period to

    prevent underestimation of TAT.

  • 20

    5. Recommendation to Fruitvale The availability of information ranging from the companys background,

    organizational structure, operating procedures and the companys performance is

    utilised for revising and modifying the company strategy and policy. This information

    serves as roadmap for the recommendation for further improvement.

    The proposed recommendations for solving the identified issues are discussed in

    detail in this section. The discussions for each recommendation include the related

    issue, the recommendation proposal and its effect toward further improvement.

    Lastly, a matrix diagram is included as the basic guideline on the significance of

    recommendation toward further improvement.

    5.1. FIFO System and Penalty Related issue:

    The teams in different department are currently prioritising the incoming

    request, thus the policy is violated.

    Recommendations toward the issue:

    Emphasise the criticality of FIFO policy

    Emphasise the importance of customer satisfaction, not the premium

    generated by the policy

    Introduce supervision system to ensure the policy is followed, and allocate

    penalty

    Effects toward improvement:

    Reduces the non-value added activities, such as sorting

    Reduces the renewal late and lost due to the elimination of prioritisation.

    Reduces TAT

    Improve the net income

  • 21

    5.2. Revaluate Turnaround Time Computation Related issue:

    The high turnaround time is a main competitive disadvantage for the branch.

    Recommendations toward the issue:

    Revaluate the method in estimating TAT due to some issues in the

    computation that have been addressed previously. The additional information

    for correct TAT computation can be obtained by benchmarking the

    computation.

    Revaluate the input data for estimating TAT.

    The effect toward improvement:

    Improvement of TAT in term of low TAT and its accuracy

    5.3. Revaluate Salary/Plus System Related issue:

    The introduction of Salary Plus system leads prioritisation of new policy since

    the incentive will be paid only for each new policy written about quota.

    Recommendation toward the issue:

    The incentive will be paid for all policy written above quota. This action will

    increase the operating expenses, but the benefits, in term of improvement in

    revenue, will overcome the increase in expenses.

    Effects toward improvement:

    Enhancing the FIFO policy

    Reduces the renewal late rate

    5.4. Revise the Agents Commission Related issue:

    The significant gap of renewal commission (7%) and new policy (25%)

    motivates the agent to focus on getting a new customer despite of the quality

    of the client.

    Recommendation toward the issue:

    Decrease the gap between the commissions by increasing the commission of

    renewal policy.

  • 22

    Effect toward improvement:

    The good quality customer will reduce ordinary insured losses, thus improving

    the branchs profitability.

    5.5. Revise the Terrorise Strategy Related issue:

    The division of territory strategy is introduced to improve the responsiveness,

    but this strategy in fact increases the renewal lost, thus it is ineffective.

    Recommendation toward the issue:

    Bringing the underwriting teams together in order to centralised the policy

    processing.

    Effect toward improvement:

    Even and balance workload for employee

    Reduce the TAT due to better resource utilisation

    5.6. Guideline for Computerised System Related issue:

    The implementation of computerised system to ensure on time RERUN

    processing is not effective due to lack of guideline.

    Recommendation toward the issue:

    Establish the clear guideline in regard to receiving and processing RERUNs

    that are generated by the computerised system

    Effect toward improvement:

    Prevent unnecessary delay of RERUN process, thus reducing the renewal late.

    5.7. Data Management System Related issue:

    The out-dated data used in the TAT calculation leads to inaccurate estimation,

    thus a proper data management system needs to be implemented for the

    purpose of regular data update.

    Recommendation toward the issue:

    Implementation of data management system such that regular update from the

    main company can be obtained in a real time manner.

  • 23

    Effect toward improvement:

    Improve the accuracy and reliability of TAT calculation and other related

    computation.

    5.8. Standardise Working Procedure Related Issue:

    The large variation of the process in each department leads to high TAT

    computation.

    Recommendation toward the issue:

    Establishing a standard working procedure that provides clear guideline of the

    step-by-step procedures that need to be done for different policies in different

    department. The use of graphical representation, such as flowchart, can be

    implemented to improve the effectiveness.

    Effect toward improvement:

    The low variation of process leads to lower Standard Completion Time (SCT),

    thus it reduces the overall TAT estimation.

    5.9. Outcome The matrix diagram is constructed in order to show the priority of the

    recommendation and inform the management regarding the significance of each

    recommendation. The matrix diagram is shown in the following figure.

    Figure 11 Matrix diagram

  • 24

    Bibliography Brown, C. E. (1998). Coefficient of Variation. Applied Multivariate Statistics in

    Geohydrology and Related Science, 1998, pp 155-157

    Foster, S. T. (2013). Managing Quality: Integrating the Supply Chain (5th ed).

    Pearson Education Limited, Harlow

    Microsoft Corp. (2013). Choosing the best trendline for your data. Retrieved on April

    29, 2013 from http://office.microsoft.com/en-au/help/choosing-the-best-trendline-for-

    your-data-HP005262321.aspx

    Mieghem, P.V. (2005). General Queuing Theory. Retrieved on April 29, 2013 from

    http://www.nas.its.tudelft.nl/people/Piet/CUPbookChapters/PACUP_queueing.pdf

    Sullivan, W.G., Wicks, E.M. & Koelling, C.P. (2012). Engineering Economy (15th

    ed). Pearson Higher Education, Upper Saddle River, New Jersey

    Group 13 Final ReportGroup 13 Final Report.2Group 13 Final Report.3