---
title: "Monitoring vs controlling; EVA concept"
subject: "Project Engineering"
chapter: 4
key: "semester_7/project_engineering:monitoring-vs-controlling-eva-concept"
source: https://www.bctengineer.com/q/semester_7/project_engineering/monitoring-vs-controlling-eva-concept
site: BCT Engineering
---

# Monitoring vs controlling; EVA concept

Project Engineering · Chapter 4: Project Implementation and Controlling

- Asked in: 2068 Baisakh (old course), 8 marks
- Video: [What is Earned Value Management - EVM? PM in Under 5](https://www.youtube.com/watch?v=sAZZ5av9kk0) — Online PM Courses - Mike Clayton
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/project_engineering/monitoring-vs-controlling-eva-concept
- Whole chapter: https://www.bctengineer.com/md/semester_7/project_engineering/chapter-4

## Question

Differentiate monitoring and controlling by explaining the project control cycle. Explain the concept of Earned Value Analysis used for controlling cost.

## Short answer

Monitoring measures and reports actual progress; controlling analyses variances and acts. Earned Value Analysis uses Planned Value (PV), Earned Value (EV), and Actual Cost (AC) to compute schedule variance (SV = EV−PV) and cost variance (CV = EV−AC). SPI = EV/PV, CPI = EV/AC; SPI/CPI below 1 indicate delay or overrun, enabling corrective action.

## Answer

#### Monitoring and controlling

| Basis | Monitoring | Controlling |
|---|---|---|
| Nature | Observing, measuring and reporting progress | Acting on the findings to bring the project back to plan |
| Question | What is happening? | What should be done about it? |
| Output | Progress and variance reports | Corrective action, revised plan |
| Stage in cycle | Measure and compare | Analyse, decide and act |
| Authority | Information gathering, any level | Decision of project manager/management |

#### Project control cycle

```text
+--------------+     +------------------+
| 1 Plan:      |     | 2 Implement and  |
| baseline of  |---->| measure actual   |
| time, cost,  |     | progress         |
| quality      |     +--------+---------+
+------^-------+              |
       |                      v
+------+-------+     +------------------+
| 5 Take       |     | 3 Compare actual |
| corrective   |<----| with plan and    |
| action /     |     | find variance    |
| re-plan      |     +--------+---------+
+------^-------+              |
       |                      v
       |             +------------------+
       +-------------| 4 Analyse causes |
                     | and decide       |
                     +------------------+
```

Monitoring covers steps 2 and 3 (measure and compare); controlling covers steps 4 and 5 (analyse and act), and the cycle is repeated at every review.

#### Earned Value Analysis (EVA) for cost control

**EVA** compares the planned value (PV), the earned value (EV) and the actual cost (AC) at a status date, so that cost and schedule performance are seen in one common unit (money).

| Term | Other name | Meaning |
|---|---|---|
| BAC | Budget at completion | Total approved budget of the project |
| PV | BCWS (planned value) | Budgeted cost of the work scheduled up to the date |
| EV | BCWP (earned value) | Budgeted cost of the work actually completed = % complete x BAC |
| AC | ACWP (actual cost) | Actual money spent for the work done up to the date |

$$
\begin{aligned} SV &= EV - PV, \qquad CV = EV - AC \\ SPI &= \frac{EV}{PV}, \qquad CPI = \frac{EV}{AC} \\ EAC &= \frac{BAC}{CPI}, \qquad ETC = EAC - AC, \qquad VAC = BAC - EAC \end{aligned}
$$

| Indicator | Value | Meaning |
|---|---|---|
| SV, SPI | SV > 0, SPI > 1 | Ahead of schedule |
| | SV = 0, SPI = 1 | On schedule |
| | SV < 0, SPI < 1 | Behind schedule |
| CV, CPI | CV > 0, CPI > 1 | Under budget (cost efficient) |
| | CV = 0, CPI = 1 | On budget |
| | CV < 0, CPI < 1 | Over budget (cost inefficient) |

Example: BAC = Rs 10 lakh; at the status date PV = Rs 5 lakh, EV = Rs 4 lakh, AC = Rs 6 lakh. $SV = -1$ lakh, $CV = -2$ lakh, $SPI = 0.80$, $CPI = 0.67$, $EAC = 10/0.67 = 15$ lakh. The project is behind schedule and over budget, so corrective action is needed at once.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Which steps of the control cycle are monitoring and which controlling?
   A. Monitoring is steps 2-3 (measure and compare); controlling is steps 4-5 (analyse and act)
   B. Monitoring is analyse and act; controlling is measure
   C. Monitoring is step 5 only
   D. Both are step 1
   Answer: A. Monitoring observes and compares; controlling decides and acts. (Key point: Cycle steps)

2. How is earned value found?
   A. Actual money spent
   B. % complete x BAC
   C. Planned % x AC
   D. BAC / CPI
   Answer: B. EV is the budgeted cost of work actually completed = % complete x BAC. (Key point: EV definition)

3. What do CV < 0 and CPI < 1 indicate?
   A. Under budget
   B. Over budget (cost inefficient)
   C. On budget
   D. Ahead of schedule
   Answer: B. CV = EV - AC and CPI = EV/AC below the neutral values mean cost overrun. (Key point: Indices)

4. BAC = 10 lakh, PV = 5, EV = 4, AC = 6 lakh. What are SPI and CPI?
   A. SPI = 0.67, CPI = 0.80
   B. SPI = 1.25, CPI = 1.5
   C. SPI = 0.80, CPI = 0.67
   D. SPI = 0.80, CPI = 1.2
   Answer: C. SPI = 4/5 = 0.80; CPI = 4/6 = 0.67. (Key point: Example numbers)

## Related in Project Engineering

- [Cost control need; earned value; EVA approach](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Acost-control-necessary-eva-approach) — Project Engineering, chapter 4
- [Monitoring, evaluation, controlling and life cycle](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Amonitoring-evaluation-controlling-life-cycle) — Project Engineering, chapter 1
- [Monitoring, evaluation, control; control cycle](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Adefine-monitoring-evaluation-control-cycle) — Project Engineering, chapter 4, asked 4×
- [Cost control; EVA 15 houses in 3 months](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aeva-houses-15-in-3-months) — Project Engineering, chapter 4
- [Short note: Earned value analysis](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aearned-value-analysis-note) — Project Engineering, chapter 4
- [Monitoring and quality, cost, schedule control](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Amonitoring-quality-cost-schedule-control) — Project Engineering, chapter 4

## Related in other subjects

- [Earned value analysis for performance control](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Aeva-performance-control) — Construction Management, chapter 7, asked 6×
- [Earned value management](https://www.bctengineer.com/question.md?key=semester_7%2Fict_project_management%3Aevm) — ICT Project Management, chapter 9
- [Cost vs value; factors affecting valuation](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Acost-vs-value-factors) — Construction Management, chapter 13
- [Time cost trade-off concept with example](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Atcto-concept) — Construction Management, chapter 2, asked 5×