Earned Schedule_Walt Lipke

8/9/2019 Earned Schedule_Walt Lipke

1/27

1International Metrics Congress

2007

Earned Schedule …a n em e r g i n g e n h a n c e m e n t t o E VM

Walt Lipkebrought to you by the PMI MetSIG and Cheetah Learning


2/27


2007

Brought To You By

Cheetah Learning is Global Leader in PMP Examprep and PM Training with classes covering theglobe from the U.S. and Canada to SouthAmerica, Europe, New Zealand and Australia,India and Asia, the Middle East and Africa.

Our accelerated learning techniques speedlearning and retention and drive our 97% passrate on the PMP exam.

Michelle LaBrosse, Founder & Chief Cheetah,recently named one of 25 Influential Women inPM in the world.

Cheetah Learning strives to raise the profile of PM with our webinars and our Know HowNetwork column which is published in over 200publications around the world.


3/27


2007

Objective

• Introduce the Earned Schedule Concept

• Develop the Schedule Indicators

• Apply to Project Duration Prediction

• Apply to Schedule Analysis


4/27


2007

Earned Value Basics

Time

$$

PVEVSPI

ACEVCPI

BAC

PV

AC

EV

SV

CV


5/27


2007

EVM Schedule Indicators

• SV & SPI behave erratically for projects behind schedule

– SPI im pro ves and equals 1.00 at end of pr oject

– S V im p r o v e s an d c o n c lu d e s a t $0 v ar ia n c e

• Schedule indicators lose predictive ability over the last third

of the project


6/27


2007

EVM Schedule Indicators

• Why does this happen?

– SV = EV – PV

– SPI = EV / PV

• At planned completion PV = BAC

• At actual completion EV = BAC• When actual > planned completion

– SV = BAC – BAC = $000

– SPI = BAC / BAC = 1.00

Regardless of lateness !!


7/27


2007

Earned Schedule Concept

The cumulative value of ES is

found by using EV to identify

in which increment of PV the

cost value occurs.

7 months gone by, but the project only has “Earned Schedule” to Month 5W h i c h S V “A n s w e r s th e ma i l ? ” $ b eh i n d o r 2 mo n th s b e h i n d s c h e d u l e ?

$

5

Σ PV

Σ EV

Time Now

71 2 3 4 6 8 9 10

A

B

SVc

SVtES


8/27


2007

Earned Schedule Metric

• Required measures

– Performance Measurement Baseline (PMB) – thetime phased planned values (PV) from project start tocompletion

– Earned Value (EV) – the planned value which has

been “earned” – Actual Time (AT) - the actual time duration from the

project beginning to the time at which project status isassessed

• All measures available from EVM


9/27


2007

Earned Schedule Calculation

• ES (cumulative) is the:Number of completed PV time increments EV exceeds +the fraction of the incomplete PV increment

• ES = C + I where:C = number of time increments for EV PV

I = (EV – PVC) / (PVC+1 – PVC)


10/27


2007

Interpolation Calculation

$$

I /1 mo = p / q

I = (p / q) 1 mo

p = EV – PVCq = PVC+1 – PVC

I = 1moEV – PVC

PVC+1 – PVC

PVC+1

ES(calc)

EV

PVC

ES

JulyJuneMay

1 mo

I

p

q

Time


11/27


2007

Earned Schedule Indicators

• Schedule Variance:

SV(t) = ES – AT

• Schedule Performance Index:

SPI(t) = ES / AT

where AT is “Actual Time” – the duration from start to time now

• SV(t) and SPI(t) are time-based (months, weeks …)


12/27


2007

Earned Schedule Indicators

• What happens to the ES indicators, SV(t) & SPI(t), when theplanned project duration (PD) is exceeded (PV = BAC)?

They Still Work …Correctly!!• ES will be PD, while AT > PD

– SV(t) will be negative (time behind schedule) – SPI(t) will be < 1.00

Reliable Values from Start to Finish !!


13/27


2007

Schedule Variance Comparison

-400

-300

-200

-100

0

J F M A M J J A S O N D J F M

-3

-2

-1

0

0

20

40

60

80

100


0

0.2

0.4

0.6

0.8

1

SV($) SV(t)

Early Finish Project

Late Finish Project

$ Mo

$ Mo


14/27


2007

Schedule Index Comparison

0.98

1.00

1.02

1.04

1.06

1.08

1.10

1.12


0.70

0.80

0.90

1.00

1.10

1.20

1.30


SPI($) SPI(t)

Early Finish Project

Late Finish Project


15/27


2007

Commercial IT Infrastructure Expansion Project Phase 1

Cost and Schedule Variances

at Project Projection: Week Starting 15th July xx

-160

-140

-120

-100

-80

-60

-40

-20

0

20

1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 5 16 17 18 19 20 21 22 23 24 25 26 27 2 8 29 30 31 32 33 34

Elapsed Weeks

D o l l a r s ( , 0 0 0 )

-16

-14

-12

-10

-8

-6

-4

-2

0

2

W e e k s

CV cum SV cum Target SV & CV SV (t) c um

Stop wk 19

Re-start wk 26Sched wk 20

Late Finish Project


16/27


2007

Earned Schedule – Key Points

• ES Indicators constructed to behave in an analogousmanner to the EVM Cost Indicators, CV and CPI

• SV(t) and SPI(t)

– Not constrained by PV calculation reference

– Provide duration based measures of schedule

performance – Valid for entire project, including early and late finish

• Facilitates integrated Cost/Schedule project management

(using EVM with ES)


17/27


2007

Schedule Prediction

• Can the project be completed as planned? – TSPI = Plan Remaining / Time Remaining

= (PD – ES) / (PD – AT)where PD is the planned duration (time at BAC)

(PD – ES) = PDWRPDWR = Planned Duration for Work Remaining

• …completed as estimated? – TSPI = (PD – ES) / (ED – AT)

where ED = Estimated Duration

Not Achievable 1.10 Achievable 1.00

Predicted OutcomeTSPI Value


18/27


2007

Schedule Forecasting

• Long time goal of EVM …Prediction of total project durationfrom present schedule status

• Independent Estimate at Completion (time)

– IEAC(t) = PD / SPI(t)

– IEAC(t) = AT + (PD – ES) / PF(t)where PF(t) is the Performance Factor (time)

– Analogous to IEAC used to predict final cost

• Independent Estimated Completion Date (IECD)

– IECD = Start Date + IEAC(t)


19/27


2007

Earned Schedule Terminology

at Completion (time)

Independent Estimate

Performance Index

To Complete Schedule

Schedule PerformanceIndex

Schedule Variance

Actual Time

Earned Schedule

IEAC(t) = AT + (PD– ES) / PF

IEAC(t) = PD / SPI(t)IEAC(t)Predictors

TSPI(t) = (PD – ES) / (ED – AT)

TSPI(t) = (PD – ES) / (PD – AT)TSPI(t)

SPI(t) = ES / ATSPI(t)Indicators

SV(t) = ES - ATSV(t)

AT = number of periods executedATcum

ES = C + I number of completeperiods (C) plus an incompleteportion (I)

EScumMetrics

at Completion (time)

Independent Estimate

Performance Index

To Complete Schedule

Schedule PerformanceIndex

Schedule Variance

Actual Time

Earned Schedule

IEAC(t) = AT + (PD– ES) / PF(t)

IEAC(t) = PD / SPI(t)IEAC(t)Predictors

TSPI(t) = (PD – ES) / (ED – AT)

TSPI(t) = (PD – ES) / (PD – AT)TSPI

SPI(t) = ES / ATSPI(t)Indicators

SV(t) = ES - ATSV(t)

AT = number of periods executedATcum

ES = C + I number of completeperiods (C) plus an incompleteportion (I)

EScumMetrics


20/27


2007

Independent Confirmation

• SPI(t) & SV(t) do portray the real schedule performance• At early & middle project stages pre-ES & ES forecasts of

project duration produce similar results

• At late project stage ES forecasts outperform all pre-ESforecasts

• The use of the SPI(t) in conjunction with the TSPI(t) hasbeen demonstrated to be useful for managing the schedule

Stephan Vandevoorde – Fabricom Airport Systems, Belgium


21/27


2007

Schedule Analysis with EVM?

• Most practitioners analyze schedule from the bottom upusing the network schedule, independent from EVM

….“It is the only way possible.”

– Analysis of the Schedule is overwhelming

– Critical Path is used to shorten analysis(CP is longest path of the schedule)

• Duration prediction using Earned Schedule provides amacro-method similar to the method for estimating Cost

– A significant advance in practice

• But, there’s more that ES facilitates ….


22/27


2007

Facilitates Drill-Down Analysis

• ES can be applied to any level of the WBS, to include taskgroupings, such as the Critical Path (CP) – Requires creating PMB for the area of interest

– EV for the area of interest is used to determine its ES

• Enables comparison of forecasts, total project (TP) to CP

– Desired result: forecasts are equal

– When TP forecast > CP forecast, CP has changed

– When CP > TP, possibility of future problems


23/27


2007

ES Bridges EVM to the Schedule

$$

Time

PV

BAC

PD

EV

ES AT AT

SV(t)


24/27


2007

How Can This Be Used?

• Tasks behind – possibility of impediments or constraints canbe identified

• Tasks ahead – a likelihood of future rework can be identified

• The identification is independent from schedule efficiency

• The identification can be automated

PMs can now have a schedule analysis toolconnected to the EVM Data!!


25/27


2007

Current Usage & Recognition

• EVM Instructors – Performance Management Associates, Management Technologies,

George Washington University, University of Florida …

• Boeing Dreamliner , Lockheed Martin, US StateDepartment, Secretary of the Air Force

• Several Countries - Australia, Belgium, United Kingdom,

USA ….(Japan, Switzerland, Sweden, Spain, Brazil, India, …)• Applications across weapons programs, construction,

software development, …• Range of project size from very small and short to extremely

large and long duration• Inclusion of Emerging Practice Insert into PMI - EVM

Practice Standard (2004)


26/27


2007

Summary

• Derived from EVM data … only• Provides time-based schedule indicators

• Indicators do not fail for late finish projects

• Application is scalable up/down, just as is EVM

• Schedule prediction is better than any other EVM methodpresently used

• Application is growing in both small and large projects

• Practice recognized as “Emerging Practice”

• Facilitates bridging EVM analysis to include the Schedule


27/27


2007

Thank You!

Walt Lipke

Email: [email protected]

Thank You from the MetSIG…TheInformation Highway For the Metricsof the World

Earned Schedule_Walt Lipke

Documents

Transcript of Earned Schedule_Walt Lipke