Distribution Curves

A distribution curve decides how a line item's total is spread across its months. The total never changes — only its shape does. Pick the curve that best matches how the work (or the money) actually flows.

Cashflow Manager offers Procore's built-in curves plus several custom curves.

Built-in curves

Curve	Identifier	Shape	Best for
Linear	linear	Equal amount every month	Steady, even work; the safe default
Front loaded	front_loaded	More early, tapering off (exponential decay)	Mobilisation, early procurement, upfront deposits
Back loaded	back_loaded	Less early, building up later	Fit-out, commissioning, closeout, retention-heavy tails
Bell	bell	Peak in the middle, tapering both ends (Gaussian)	Trades that ramp up and wind down symmetrically
Manual	manual	Whatever you type per month	Irregular, one-off patterns with no underlying shape

Custom curves

Curve	Identifier	Shape	Parameters
S-curve	s_curve	Slow start → rapid middle → slow finish (logistic)	inflection (0–1, where the midpoint sits), steepness (1–15, how sharp the ramp)
Linear ramp	linear_ramp	Ramp up → steady plateau → ramp down	rampUpMonths, rampDownMonths
Custom percentages	custom	Exactly the % you set each month	percentages[] (should total ≈ 100%)

S-curve presets

The S-curve is the workhorse for construction cash flow. Rather than tuning the parameters by hand, you can pick a preset:

Preset	Inflection	Steepness	Character
Slow Start	0.3	8	Gentle beginning, peaks late
Balanced	0.5	10	Symmetric S — a good general default
Fast Start	0.7	8	Quick ramp-up, peaks early
Aggressive	0.5	15	Steep, sharp transition through the middle
Gradual	0.5	6	Gentle curve, slow transition

Part-month proration

Real line items rarely start on the 1st or finish on the last day of a month. Every curve scales the first and last months by the fraction of days the line item is actually active in that month.

For example, a line item running 15 Jan → 31 Mar:

Month	Active days	Weight
January	17 of 31	≈ 0.55
February	28 of 28	1.00
March	31 of 31	1.00

The curve is calculated across the weighted months, so the part-month at each end receives a correspondingly smaller share — and the total still ties out to the line item's forecast-to-complete.

How curves push to Procore

When you activate a cost forecast, Cashflow Manager writes the periods into Procore's Advanced Forecasting. Procore's built-in curves map directly. The custom curves (s_curve, linear_ramp, custom) don't exist in Procore, so they're exported as manual with the exact monthly amounts already calculated — Procore sees the same numbers, just as explicit periods.

Choosing a curve

• Don't know? Start with S-curve (Balanced) — it matches most construction spend and income.
• Even, steady work (e.g. ongoing preliminaries): Linear.
• Heavy at one end: Front loaded (mobilisation) or Back loaded (closeout).
• Symmetric ramp: Bell.
• Known mobilisation/demob windows: Linear ramp.
• You have the exact split: Custom percentages or Manual.

Whatever you choose, you can still fine-tune individual months afterwards — see the forecasting editor.