How to Find the Slope of a Trend with SLOPE

SLOPE tells you how much one thing changes for each one-unit change in another — like the cost of each extra unit produced.

You will learn to

• Find the cost of one extra unit with SLOPE
• Scale a slope to a more readable unit
• Use SLOPE on a calculated ratio to spot economies of scale

How it works

SLOPE(known_ys, known_xs) fits the best straight line through your data (least squares) and returns its slope: how much y changes, on average, when x goes up by one. Regress total cost on units produced and the slope is the variable cost per unit — the cost of making one more.

The y range comes first. Multiply the slope to express it in friendlier units (per 100 units, per 1,000 visitors), and remember that a slope describes association within the range of your data, not a guaranteed cause.

=SLOPE(C2:C9,B2:B9)