Slope from the first to the last value: what it means and how to read it
In the report: slope — (last value − first value) / (n − 1), in row order; empty for fewer than 2 values, 0 for a constant.
How to read it
The average change from one row to the next, from the first and last values only — a quick trend of data in time order. For a least-squares line against another column use regressionSlope.xCol (xCol — the name of the other column).
In plain words
A cafe owner wrote down the cups sold on five days in a row, from Monday to Friday. She wanted to know how fast sales were growing. She sold 100 cups on Monday and 120 on Friday. She asked for slope and got 5. Now she can say that on average she sold 5 cups more with each day that passed. This number looks only at the first and the last day, so it is a quick look at which way things go. To draw a line through all the days against another column, use regressionSlope followed by the name of that column.
Where you see it
STATS_DESCRIPTIVE— Column-wise descriptive statistics with flexible metric selection and optional column filtering.
Related values
- Sum of squared values — The sum of the squared values: Σ x²; empty for a column without a single number.
- Sum of squared deviations — The sum of the squared deviations from the mean: Σ (x − x̄)²; empty for a column without a single number, 0 for one value.
- Inverse-variance weight — n / variance; empty for a column without spread or with fewer than 2 values.
- z-score of a value — The z-score of the value v: (v − mean) / std; 0 for a column without spread; empty without v.
- Weighted mean — The weighted mean with the weights in the column weightsCol, row by row; a zero, negative or missing weight leaves the row out, as SPSS WEIGHT. Empty when no row has a usable weight.
Get it in your sheet
One formula in a cell gives the whole report, Slope from the first to the last value included. ALS Stats is a free add-on for Google Sheets™.
Install ALS Stats from Google Workspace Marketplace (opens in a new tab)