234- Burn and Velocity Charts

Burn Charts Overview

• Essential agile tracking visuals; always appear on ACP exams.
• Two main types:
  • Burn Up Chart
  • Burn Down Chart

Burn Up Chart

• Tracks work completed over time.
• Axes: X = iteration/sprint; Y = cumulative story-points finished.
• Lines:
  • Scope line: total points; may rise if scope increases (e.g., 100 \rightarrow 120 points).
  • Progress line: points actually completed each iteration.
• Reading tip: vertical value at any iteration = total points done.
• Use when asked “How much work has been finished?”

Burn Down Chart

• Tracks work remaining over time.
• Axes: X = time units (days/sprints); Y = story-points left.
• Lines:
  • Blue/ideal: planned burn rate.
  • Red/actual: real burn rate.
• Reading tip: vertical value at any day = points left to do.
• Use when asked “How much work is still outstanding?”

Velocity Chart

• Shows team’s story-points completed per iteration.
• Pattern typically stabilizes after several sprints (team “finds its groove”).
• Average height of bars = team velocity.
  • Example: iterations level off near 16\text{–}17 points ➔ velocity \approx 17.
• Planning use: select backlog items whose total points ≤ velocity for next sprint.

Common Exam Calculation

• Given: average velocity = 18 points/iteration.
• Backlog: 250 remaining points.
• Required iterations = \lceil 250 / 18 \rceil \approx 14.
• Each iteration lasts 1\text{–}4 weeks ➔ project duration estimate = 14 iterations × iteration length.

Exam Tips

• Memorize: “Up = completed, Down = remaining.”
• When a question mentions showing progress done ➔ choose Burn Up.
• When a question mentions work left ➔ choose Burn Down.
• Velocity questions often test: average calculation, iterations needed, or capacity planning.
• Expect at least one scenario requiring interpretation of these charts without showing the actual graphic—recognize them by description.