A reviewer cannot read every line of a trial balance, but anything that jumped more than a set percentage deserves a look. This recipe compares each account to the prior month, flags moves beyond a threshold and treats a zero prior month as always worth checking.
2,400 to 3,100 is a 29.2% rise, which exceeds a 15% threshold and returns CHECK.
The example
Three accounts against a threshold. Both increases and decreases beyond the threshold are flagged.
| A | B | C | D | E | F | |
|---|---|---|---|---|---|---|
| 1 | Case | Prior | Current | Threshold | Flag | Change % |
| 2 | Supplies | 1,000 | 1,080 | 15.0% | OK | 8.0% |
| 3 | Freight | 2,400 | 3,100 | 15.0% | CHECK | 29.2% |
| 4 | Utilities | 560 | 410 | 20.0% | CHECK | -26.8% |
The formula
Percent change is current over prior minus one; the ABS makes decreases count too:
How it works
Here is the logic, one piece at a time:
B2=0handles a zero prior month so you never divide by zero.C2/B2-1is the percent change from last month to this month.ABS(...)ignores direction so large drops are flagged as readily as large jumps.- Comparing to the threshold in
D2returns CHECK or OK, which a filter can then isolate.
Tune the threshold by account type: payroll moves a little, marketing spend moves a lot.
Try it: interactive demo
Enter last month, this month and the threshold.
Variations
Add an absolute dollar floor
Ignore changes smaller than a dollar amount so tiny accounts do not flood the report.
Highlight with conditional formatting
Apply a rule to the flag column that turns CHECK red.
Pitfalls & errors
Without the zero guard, a new account with no prior month returns #DIV/0!.
A seasonal business will trip the flag every December; compare to the same month last year instead.
Sort the flagged rows by dollar change so the biggest items appear first.
Practice workbook
Frequently asked questions
What threshold should I use?
Why flag decreases?
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