GROWTH Function in Microsoft Excel: Syntax, Examples & Troubleshooting
Predict an Excel exponential curve with GROWTH. Reproduce a 10% growth dataset, understand optional x values and const, and handle nonpositive inputs and extrapolation risk.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: GROWTH fits an exponential relationship y = b×m^x and returns y predictions. It is appropriate for investigating multiplicative change, whereas a linear model describes additive change. Positive input y values are required for the documented exponential fitting method.
Syntax and arguments
=GROWTH(known_y's, [known_x's], [new_x's], [const])
Known y is required. Known x defaults to 1,2,3,… when omitted. New x defaults to known x when omitted, so the output then contains fitted values at observed positions. If both x arguments are omitted, both use the same sequential index.
const TRUE or omitted estimates b normally. FALSE forces b = 1 and refits the multiplicative coefficients. It does not set b to zero; doing that would make the entire exponential model zero.
The documented #NUM! condition is any zero or negative known y value. Do not add an arbitrary constant to every y merely to evade this error without acknowledging that you have changed the modeled relationship.
Worked example: project a controlled 10% increase
Enter the following data:
| Row | A · Period | B · Units |
|---|---|---|
| 2 | 0 | 100 |
| 3 | 1 | 110 |
| 4 | 2 | 121 |
| 5 | 3 | 133.1 |
- Enter new periods 4 and 5 in D2:D3.
- Enter
=GROWTH(B2:B5,A2:A5,D2:D3)in E2, reserving two output rows. - Expected predictions: 146.41, 161.051, apart from ordinary numerical rounding.
The independent model is 100×1.1^x. Each increase is 10% of the preceding value; the absolute increments are not constant. These synthetic observations lie exactly on the model, making them useful controls before trying noisy data.
Second example: return fitted values rather than new predictions
=GROWTH(B2:B5,A2:A5) returns expected values 100,110,121,133.1 at the original x values. In this exact model they match the inputs. With real noisy observations, fitted values generally differ from the observed y values.
Do not omit known x merely because your rows are evenly spaced: this example begins at 0, while the omitted x convention begins at 1. The fitted curve can compensate through b, but numerical x coordinates for later predictions must stay consistent with the model you actually supplied.
Advanced application: choose const FALSE only for a unit baseline
Use a separate fixture with x values 1,2,3 in H2:H4, y values 2,4,8 in I2:I4 and new x 4 in H6. =GROWTH(I2:I4,H2:H4,H6,FALSE) is expected to return 16. This dataset follows 1×2^x, so forcing b to 1 is consistent with its construction.
Forcing b to 1 in the first dataset would instead impose a unit value at x=0 rather than its known baseline of 100. The coefficients would need to change; the option is not a way to remove an unwanted displayed constant while preserving the same predictions.
A multiplier m = 1.1 means 10% growth per x unit, not 110% growth. If x is months, that is a per-month model; changing x units changes the coefficient’s interpretation. Extrapolation assumes that the fitted relationship continues, and this function does not independently validate that assumption or account for capacity limits and seasonality.
Array entry and data-shape checks
In a current Microsoft 365 build with dynamic arrays, enter the formula in the top-left output cell and press Enter, leaving enough empty cells for its result. In a legacy array workflow, select the intended output range first and confirm the formula with Ctrl+Shift+Enter. Excel inserts the braces; do not type them manually.
Keep each observed y paired with the corresponding x row. A single predictor requires matching x/y dimensions. For multiple predictors, a column of y observations uses one x column per predictor; a row of y observations uses one x row per predictor. New prediction inputs must retain the same predictor layout. Headers are not observations.
A blocked dynamic-array destination can produce #SPILL!, while incomplete legacy output selection can hide results. The reviewed function page does not provide a complete invalid-shape/error/coercion table, so no cross-application error behavior is assumed here. Inspect missing, text and erroneous source values rather than silently replacing them with zeros.
Compatibility and verification
Microsoft’s reference checked on October 17, 2026 lists: Excel for Microsoft 365 Excel for Microsoft 365 for Mac Excel 2024 Excel 2024 for Mac Excel 2021 Excel 2021 for Mac Excel 2019 Excel 2016. This current support list does not establish the first release. The introduction version and last functioning version have not been established from the reviewed documentation. No retirement is asserted.
Example verification: Expected numerical results are independently calculated; text and shape expectations follow the documented contract. These examples have not been tested in Microsoft Excel. No screenshot or native execution is claimed.
Related guides and source
EXP in Excel | LN in Excel | POWER in Excel | FORECAST-LINEAR in Excel
- Microsoft GROWTH reference, retrieved October 17, 2026.