Learning Center
Float Erosion and Negative Float: Early Warning Signs
A single schedule update showing 6 days of float doesn’t look alarming on its own. The same 6 days, seen as the fourth consecutive drop from an original 22, is a very different signal -- one that only shows up when you look across updates, not at any one of them in isolation.
Float Is a Trend, Not Just a Number
Total float tells you how much cushion an activity has right now. It doesn’t, by itself, tell you whether that cushion is stable, growing, or steadily being consumed. A schedule can show “10 days of float, no problem” in a single snapshot while actually being three consecutive monthly updates into a steady decline that will cross zero the month after next if nothing changes.
Worked Example: Watching the Trend Cross Zero
A single activity’s total float, tracked across five monthly updates on a fictional project:
| Update | Total Float (days) |
|---|---|
| Update 1 (Jan) | 22 |
| Update 2 (Feb) | 14 |
| Update 3 (Mar) | 6 |
| Update 4 (Apr) | -3 |
| Update 5 (May) | -11 |
By Update 3, this activity still technically “passes” a single-snapshot negative float check -- 6 days is still positive. But the erosion rate (roughly 8 days lost per update) was already established by that point, and a straight-line projection would have flagged the crossing into negative float a full update before it actually happened.
Claims Digger tracks float for every activity across every schedule update you upload -- not just the current snapshot’s single value -- so an erosion pattern like this one is visible as a trend, not something you’d have to notice by comparing several past reports by hand. See how it works.
Frequently Asked Questions
- Is negative float always a serious problem?
- It always means the schedule's own logic and durations show the project finishing later than a required or contractual date -- that's the DCMA 14-point assessment's Check 7, with a target of zero. How serious it is in practice depends on the size of the negative number and how much recovery capacity remains, but the schedule itself is telling you a real problem exists, not just flagging a formality.
- Can float erosion reverse?
- Yes -- a recovery schedule, added resources, or resequencing can restore float on a path that had been eroding. Tracking the trend across updates is exactly what lets a genuine recovery be distinguished from a temporary pause in an otherwise worsening pattern.
- Why does DCMA's high-float check matter if this article is about LOW float?
- They're catching opposite symptoms of the same underlying discipline problem: unusually high float (Check 6) often means missing logic that's hiding an activity's true relationship to the rest of the network, while eroding-toward-negative float on a genuinely well-tied activity is a real trend worth watching, not a data-quality artifact.
Part of the Claims Digger Learning Center. Related reading: The complete DCMA 14-point assessment · Total Float (glossary)