Forecast the next point
| A | B | |
|---|---|---|
| 1 | x | y |
| 2 | 1 | 3 |
| 3 | 2 | 5 |
| 4 | 3 | 7 |
| 5 | 4 | 9 |
Formula: D2: =FORECAST.LINEAR(5,B2:B5,A2:A5)
Result: 11
Extending y=2x+1 to x=5 gives eleven.
Google Sheets function
FORECAST.LINEAR in Google Sheets
FORECAST.LINEAR with worked examples you can test in the live grid. The argument details are in the Excel guide.
In Google Sheets
The arguments and common errors are covered in the FORECAST.LINEAR Excel guide; check the function help in Google Sheets for its own argument list.
Worked examples in Google Sheets
Interpolate a midpoint
| A | B | |
|---|---|---|
| 1 | x | y |
| 2 | 1 | 3 |
| 3 | 2 | 5 |
| 4 | 3 | 7 |
| 5 | 4 | 9 |
Formula: D2: =FORECAST.LINEAR(2.5,B2:B5,A2:A5)
Result: 6
The fitted line gives six halfway between x=2 and x=3.
Forecast a flat series
| A | B | |
|---|---|---|
| 1 | x | y |
| 2 | 1 | 5 |
| 3 | 2 | 5 |
| 4 | 3 | 5 |
Formula: D2: =FORECAST.LINEAR(8,B2:B4,A2:A4)
Result: 5
A horizontal fitted line predicts five at any x.
Try it
A tiny spreadsheet with example data. Edit the formula or any number and see the result.
Formula in D2: =FORECAST.LINEAR(7,B2:B7,A2:A7)
| A | B | C | D | |
|---|---|---|---|---|
| 1 | Month | Revenue | Result | |
| 2 | 1 | 120 | 194.133333333 | |
| 3 | 2 | 135 | ||
| 4 | 3 | 150 | ||
| 5 | 4 | 148 | ||
| 6 | 5 | 170 | ||
| 7 | 6 | 185 |
Result in D2: 194.133333333
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