GROWTH in Collabora Office: Predict Values from an Exponential Trend
Use Collabora GROWTH with explicit input arrays, forecast an exponential pattern, compare multiplicative growth with straight-line assumptions, and enter array results.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: For X values 0, 1, 2, 3 and Y values 3, 6, 12, 24, the exponential pattern is y=3×2Ë£. GROWTH’s independent predictions at X=4 and X=5 are 48 and 96.
Syntax and model selection
=GROWTH(DataY [; [DataX] [; [NewDataX] [; FunctionType]]])
DataY is the required observed-Y array. DataX optionally supplies the matching observed-X array. NewDataX optionally supplies the X positions at which to calculate results. FunctionType selects the model: 0 uses y=mˣ; a nonzero setting uses y=b×mˣ.
The dedicated section does not clearly specify every omitted-array/default detail. Its accompanying guidance says optional parameters should be omitted only when no later argument follows. The worked formulas therefore supply all four arguments explicitly, avoiding ambiguous empty-slot assumptions.
The exponential model is multiplicative. The multiplier m is a factor per X unit, not an additive slope. A factor of two means doubling per unit in the independent example, not adding two each time.
Example: reproduce a known exponential sequence
Enter the following in A2:B5:
| Row | A: X | B: Y |
|---|---|---|
| 2 | 0 | 3 |
| 3 | 1 | 6 |
| 4 | 2 | 12 |
| 5 | 3 | 24 |
Put 4 and 5 in D2:D3. Select E2:E3 and enter as an array:
=GROWTH(B2:B5;A2:A5;D2:D3;1)
The independently expected output is 48; 96, vertically. Check it with =3*2^D2 and fill down in a separate control column. These are independent exponential calculations, not captured native Collabora outputs.
Enter the result as an array
The Collabora page documents array entry: select the intended output range, enter the formula, and confirm with Ctrl+Shift+Enter on the corresponding platform, or use the Function Wizard with Array checked. On platforms using Command, follow the Command/Ctrl shortcut indicated by the help. Do not type the outer array-formula braces yourself.
The category guidance warns that ordinary entry can return only the upper-left value. Existing array results are edited by selecting the whole array, not by overwriting one member cell. This guide does not assume modern automatic spill behavior from another spreadsheet.
Advanced example: interpolate as well as extrapolate
Put 0.5 and 1.5 into D6:D7 and use the same observed arrays with D6:D7 as NewDataX. The independent predictions are approximately 4.242640687 and 8.485281374.
These values follow the exponential curve between observed positions. A straight-line midpoint between Y=3 and Y=6 would be 4.5, which answers a different interpolation question. Choosing GROWTH chooses an exponential shape, not a universally correct interpolation rule.
The X unit matters. If X is months, m applies per month. Replacing months with years without transforming the model changes the meaning of the estimated multiplier.
Advanced example: constrain the starting scale deliberately
FunctionType 0 fixes the multiplicative scale b at one. To check that model cleanly, create a separate dataset X=1,2,3 and Y=2,4,8. With new X 4,5 and FunctionType 0, the independent results are 16,32, because y=2Ë£ already has b=1.
Do not apply the constraint merely to reduce the number of coefficients. The earlier 3×2ˣ dataset has b=3; forcing b=1 changes the fitted curve. A constraint should reflect the intended model, not a cosmetic preference.
Diagnose fit and forecast limits
Use predictions at the original X values to inspect fit before forecasting far outside the observed range. For the exact 3×2ˣ example, the independent fitted values reproduce 3,6,12,24 and residuals are zero. Real datasets may not lie exactly on an exponential curve.
EXP and LN are related mathematical tools for understanding exponential models. A log-linear calculation needs positive Y values; the guide does not establish native handling or exact error codes for zero/negative observations.
Matching array dimensions, numeric data, and meaningful X units are essential. The source does not fully enumerate text/blank coercions, singular-data outcomes, or numerical limits. A forecast is a model projection, not a guarantee that a real process will continue multiplying at the same rate.
Availability and verification
The exact function is documented in Collabora Office 26.04 desktop help, retrieved and reviewed on October 17, 2026. This establishes a documentation scope, not the first release that introduced the function or the last version in which it works; those versions and any retirement date remain unestablished. Collabora Online and mobile support are not inferred from desktop help, nor is behavior in another spreadsheet product.
The examples are documentation-based expectations with independent calculations. They have not been executed in Collabora Office. No application screenshot or native error/coercion certification is implied. Formulas use English function names and semicolon argument separators.
References
- Collabora Office 26.04: GROWTH (checked October 17, 2026).
- Editorial testing standards.