Function flow_distribution_percent 

pub fn flow_distribution_percent(
    items_of_type: f64,
    total_completed_items: f64,
) -> Option<f64>

Flow distribution: the percentage share of one flow item type among all completed items.

Flow distribution (chapter 2.3) answers “what kind of work was it” — features, defects, risk, or debt. Report it alongside flow velocity, never alone, so a rising item count that is quietly dominated by defect rework is visible rather than mistaken for accelerating feature delivery.

Arguments

• items_of_type — count of completed items of one flow item type.
• total_completed_items — count of all completed items in the period.

Returns

Some(percentage) (e.g. 45.0 for 45%), or None when total_completed_items is zero.

Examples

use software_engineering::flow_framework::flow_distribution_percent;

// The vendor's "features" share fell from 70% to 45% while velocity rose.
assert_eq!(flow_distribution_percent(45.0, 100.0), Some(45.0));
assert_eq!(flow_distribution_percent(1.0, 0.0), None);