Introduction
Rules of credit are used to measure the progress of work completed against the planned work. The most commonly used rules of credit are;
- 0/100 – Work is considered as earned (completed) when it is 100% completed.
- 50/50 – 50% of the work is considered as earned as soon as the work starts. The remaining 50% will be considered as earned only when the remaining 50% is fully completed.
- 25/75 – 25% of the work is considered as earned as soon as the work starts. The remaining 75% is considered as completed only when 100% of the work is completed.
- 20/80 – 20% of the work is considered as earned as soon as the work starts. The remaining 80% is considered as completed only when 100% of the work is completed.
- When none is defined, we apply % completed based on actual measurement or expert judgment.
Rules of Credit – Examples
Let us see how the progress is reported based on the various rules of credits discussed above. The orange arrow indicates the review point.
0-100
| Activity | Earned Value |
| A | 0 |
| B | 0 |
| C | 0 |
| D | 500 |
| Total | 500 |
50-50
| Activity | Earned Value |
| A | 500 |
| B | 400 |
| C | 500 |
| D | 500 |
| Total | 1900 |
Summary
Defining rules of credit at the activity level during project planning is key to progress monitoring and control. The commonly used rules of credit are 0/100, 50/50, 25/75, 20/80 and percentage completion based on actual progress made.