Rollforward & time series
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
| Function | Description |
| ROLLFORWARD_ADVANCED | Projects a node into the future using driver nodes with additional optional parameters. |
| ROLLFORWARD | Projects a node into the future including the additive effects of defined driver nodes. |
| ROLLFORWARD_MUL | Projects a node into the future including the multiplicative effects of defined driver nodes. |
Cumulative and rolling calculations
| Function | Description |
| RUNNINGSUM | Calculates the cumulative sum along the time axis. |
| RUNNINGPROD | Calculates the cumulative product along the time axis. |
| MOVINGAVG | Returns the moving average over a defined time window. |
| MOVINGSUM | Returns the moving sum over a defined time window. |
| MTD (see YTD) | Returns month-to-date values as a running sum per month over the lowest time level. |
| QTD (see YTD) | Returns quarter-to-date values as a running sum per quarter over the lowest time level. |
| YTD | Returns year-to-date values as a running sum per year over the lowest time level. |
| WTD (see YTD) | Returns week-to-date values as a running sum per week over the lowest time level. |
Timing and loop logic
| Function | Description |
| TIMELAG | Applies time-lagged effects at a given time granularity to model delays or growth curves. |
| STRETCH_CURVE | Stretches curves along the X-axis by a factor, starting at 0 by default or at a specified X position. |
| SCHEDULEPROJECTS | Calculates a project KPI over time based on each project’s timing. |
| PREVIOUS | Returns the previous period’s value, except at a base period where it takes a specified base node value, enabling loop calculations. |
Statistical forecasting
| Function | Description |
| ARIMA | Forecasts values using an autoregressive integrated moving average model. |
Choosing between similar functions
ROLLFORWARD_ADVANCED vs ROLLFORWARD / ROLLFORWARD_MUL
- Use
ROLLFORWARD_ADVANCEDwhen you need richer projection options and more control - Use
ROLLFORWARDfor additive drivers - Use
ROLLFORWARD_MULfor multiplicative drivers
MTD/QTD/YTD/WTD vs RUNNINGSUM
- Use to-date functions for totals that reset within periods
- Use
RUNNINGSUMfor 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
PREVIOUSwhen you need a base case and loop-style logic - Use
PM/PY/PQ/PWfor simple previous-period references
TIMELAG vs STRETCH_CURVE
- Use
TIMELAGfor delayed effects - Use
STRETCH_CURVEfor 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) versusMTD/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