Rollforward & time series

Overview

Use this category when you need time-based logic such as projections, running totals, moving windows, and timing effects.

These functions operate along the time axis to help you forecast values into the future, build cumulative KPIs, smooth values over time, or model delayed impacts.

Start here if…

• You want to project values forward using drivers.

• You want cumulative KPIs like YTD.

• You want rolling windows such as moving average or moving sum.

• You want to model timing effects such as delays or stretched profiles.

• You need a previous-period building block for loop logic.

Not here if…

• You want standard growth comparisons or deltas → see Compare periods

• You mainly need to reshape dimensionality → see Dimensionality & hierarchies

Mental model

• Projection: calculate future periods based on a base and driver logic

• Cumulative: sum or multiply over time, either continuously or with periodic resets

• Rolling window: aggregate across a sliding window of prior periods

• Timing effects: shift or spread impacts across time

• Loop logic: reference previous-period values with an explicit base case

Common patterns

Project values forward with drivers
ROLLFORWARD_ADVANCED('Base', 'Driver1', 'Driver2')
Use when you want a flexible driver-based projection.

Build a running total
RUNNINGSUM('Node')
Use when you want cumulative values across the full time axis.

Build a cumulative KPI with periodic reset
YTD('Node')
Use when you want cumulative totals that reset within each year.

Smooth values with a moving window
MOVINGAVG('Node', "TimeLevel", WindowSize)
Use when you want a rolling average over prior periods.

Model delayed impact
TIMELAG('Node', 'TimeLagNode', "TimeLevel")
Use when an effect should appear after a delay.

Use previous-period logic with a base case
PREVIOUS('Node', "Level", 'BaseNode', "BaseValue")
Use when you need loop-style logic with an explicit starting point.

Functions in this category

Projection

Cumulative and rolling calculations

Timing and loop logic

Statistical forecasting

Choosing between similar functions

ROLLFORWARD_ADVANCED vs ROLLFORWARD / ROLLFORWARD_MUL

• Use ROLLFORWARD_ADVANCED when you need richer projection options and more control.

• Use ROLLFORWARD for additive drivers.

• Use ROLLFORWARD_MUL for multiplicative drivers.

MTD/QTD/YTD/WTD vs RUNNINGSUM

• Use to-date functions for totals that reset within periods.

• Use RUNNINGSUM for a running total across the full time axis.

MOVINGAVG/MOVINGSUM vs to-date functions

• Use moving functions for rolling windows.

• Use to-date functions for cumulative totals within the current period.

PREVIOUS vs Compare periods shortcuts

• Use PREVIOUS when you need a base case and loop-style logic.

• Use PM/PY/PQ/PW for simple previous-period references.

TIMELAG vs STRETCH_CURVE

• Use TIMELAG for delayed effects.

• Use STRETCH_CURVE for stretching/compressing a profile.

Pitfalls & troubleshooting

• Future periods are missing in projections: confirm the base series has values in the last actual period and drivers are defined for the projection range.

• Projection results look wrong: validate the base node and each driver node separately, then add drivers back one by one.

• Cumulative totals are too large: confirm whether you used RUNNINGSUM (no reset) versus MTD/QTD/YTD/WTD (resets).

• Moving windows look shifted: verify the time level and window definition and confirm with spot checks in Data preview.

• PREVIOUS behaves unexpectedly at the first period: verify the base case and handle missing values explicitly if needed.

• Timing effects feel wrong: confirm the time granularity and whether you need a lag (TIMELAG) versus a profile stretch (STRETCH_CURVE) or project scheduling (SCHEDULEPROJECTS).

Related sections

• Compare periods: standard growth comparisons and previous-period shortcuts

• Dimensionality & hierarchies : prepare output shape or create empty simulation space

• Troubleshooting guide: missing values and unexpected results

• Function catalog: full signatures, parameters, and examples