Cumulative Flow Diagram | Identify Bottlenecks

GitScrum's CFD shows task distribution across columns over time. Widening bands indicate bottlenecks. Consistent band width shows healthy flow and WIP balance.

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How to read GitScrum Cumulative Flow diagram?

GitScrum's Cumulative Flow Diagram (CFD) shows task distribution across columns over time. Horizontal axis is time, vertical is task count. Each colored band represents a column. Widening bands indicate bottlenecks. Consistent band width shows healthy flow. CFDs help identify where work accumulates and flow problems exist [Source: Kanban metrics].

Reading the CFD:

Access Reports - Navigate to GitScrum Reports

Select Cumulative Flow - Choose CFD report

Set date range - Select time period

Read bottom to top - Done is at bottom

Identify bands - Each color is a column

Look for patterns - Widening/narrowing bands

CFD band interpretation

Pattern	Meaning	Action
Widening band	Bottleneck	Add capacity or reduce inflow
Narrowing band	Draining	May need more input
Consistent width	Healthy flow	Maintain current process
Sudden spike	Batch arrival	Avoid batch work
Flat top	No new work	Check backlog health

Key CFD metrics

Metric	How to Read
Lead time	Horizontal distance, task entry to done
WIP	Vertical height of active bands
Throughput	Slope of Done area
Bottleneck	Widest expanding band
Flow efficiency	Ratio of active to wait time

CFD health indicators

Indicator	Healthy	Unhealthy
Band width	Consistent	Widening
Done growth	Steady	Flat
Total WIP	Stable	Increasing
Wait columns	Thin	Wide
Flow	Smooth	Erratic

Common CFD patterns

Pattern	Description	Solution
Bulging middle	Work stuck in progress	Lower WIP limits
Flat done	Nothing completing	Unblock bottleneck
Staircase	Batch delivery	Flow more continuously
Widening review	Slow reviews	Add reviewers
Growing backlog	Too much input	Prioritize ruthlessly

Using CFD for improvement:

Identify bottleneck - Find widening band

Analyze root cause - Why is it widening?

Take action - Add capacity or reduce input

Monitor change - Watch band width

Iterate - Continuous improvement

CFD vs other metrics

Metric	Shows	CFD Shows
Velocity	Points per sprint	Flow over time
Burndown	Remaining work	Work distribution
Cycle time	Single task speed	System flow
Throughput	Completion rate	Everything together

CFD time ranges

Range	Use Case
1 week	Daily flow patterns
2 weeks	Sprint analysis
1 month	Trend identification
3 months	Process improvement

Best practices

Practice	Reason
Check weekly	Catch problems early
Compare periods	See improvement
Share with team	Collective ownership
Act on insights	Don't just observe
Combine with WIP limits	Prevention + detection