SmoothForecast

Syntax

SmoothForecast(Year1, Value1, Year2, Value2,... YearN, ValueN) or
SmoothForecast(ExcelFile, ExcelRange)
SmoothForecast(LCDS, SeriesName, Filter1, Filter2, [CountryISO3])
SmoothForecast(Branch:Variable)

See also: Using Time-Series Functions and Specifying Excel File and Range Parameters

Summary

Forecasts future values based on a smooth curve polynomial function of the form

Y = a + b.X + c. X2 + d. X3 + e.X4 + ...

When more points are available, a higher degree polynomial is used to give a more accurate fit. A minimum of 3 year/value pairs are required in order for the curve to be estimated.  

The second syntax of the function retrieves years and values from a specified Excel file and range. The third syntax of the function retrieves years and values from the online LEAP Cloud Data Server (LCDS). In both cases, retrieving this data initially may takes some time (typically a second or less depending on your internet connection), but thereafter values are cached locally for near-instant retrieval.  Use the Time-Series wizard to help specify the parameters required when using these syntax.