Look back two rows

sql

SELECT month,
       signups,
       LAG(signups, 2) OVER (ORDER BY month) AS signups_2_months_ago
FROM monthly_signups;

Explanation

Offsets larger than 1 are useful for month-over-month or quarter-over-quarter comparisons.

Learn the surrounding workflow

Compare similar commands or jump into common fixes when this command is part of a bigger troubleshooting path.

Same sheet · prioritizing LAG and LEAD basics

Pull the previous value in order.

Open In sheetsqlsame section

Preview the next value in sequence.

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Avoid NULL on the first row.

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Subtract the previous day's value.

Compute relative change versus previous row.

Measure time since the prior event.