Illustrative modelData governance · Relevant to Automation, Fleet finance

Checks before leadership sees a number

A report is only as good as the match between the systems behind it. This build uses two invented systems. It finds a large break in a full-year figure, locates it by month and engine, and shows what a loose tolerance would have let through.

What this shows

Field by field: who owns it, how the two systems match, and the tolerance
A match check by month and by engine, so a break can be located
A worked case where a full-year figure is overstated by a double count
A tolerance slider showing what would have escaped

How I use it

Reviewing a number before it goes to leadership
Setting a tolerance that catches real breaks without noise
Assigning an owner to each field that feeds a report

Explore the model below. It uses an invented company and invented numbers.

Explore the model

Illustrative model · Synthetic data

Wide tables scroll sideways: swipe inside a table to see every column.

Sample build: checks on an engine cost report

Marlowe Air is an invented airline with eight engines. Its leadership report takes the year's engine maintenance cost from a maintenance cost system, and the finance ledger holds the same invoices. This page matches the two, flags any break larger than a limit you set, and locates it by month, engine and invoice.

Invented airline, systems and amounts for illustration. Figures are in thousands of dollars.

What to try

Start at a limit of $50K. The amber cells are outside it. Click the one for Engine 5 in July to see the invoices behind it.
Raise the limit to $140K and the missing invoice slips through. At $185K the wrong-engine pair goes too, at $420K the posting-month pair, and at $1,150K the double count.
Lower the limit to zero and rounding differences are flagged too, so the real breaks are harder to see.
Choose Duplicate removed under System A and the full-year break moves from +$1,027K to -$123K.

Flag a break larger than$50K

The same limit applies to each cell, each engine total, each month total and the full year. A difference at or under the limit passes.

System A

Every difference is System A less the ledger, so a plus sign means the report is higher than the books. Duplicate removed drops the second copy of a repeated invoice from System A and re-runs everything.

The two systems

System A is the maintenance cost system. The leadership report reads it. Owner: Technical operations.
The ledger is System B, the finance book of record. Owner: Fleet accounting.

Report figure, System A

$7,552K

Engine maintenance cost for the year

Ledger, System B

$6,525K

The book of record

Break, A less ledger

+$1,027K

15.7% of the ledger. Outside the limit.

Cells flagged

6 of 13

Cells that differ and are over the limit

Passed with a difference

Net +$17K

Largest break that passed

$15K

Under the $100K that matters to the report

What the check says

Hold the report. For the year, System A is $1,027K above the ledger (15.7% of it), outside the limit of $50K. 6 cells are flagged, led by Engine 5 in July at +$1,150K.

At a limit of $50K, 6 of the 13 cells that differ are flagged. The 7 that passed net to +$17K and add up to $25K counting both signs. The largest is $15K. Every flagged cell is a real break and nothing that matters passed.

By month

By engine (E1 is Engine 1)

Amber bars are outside the limit and carry their value. Blue bars differ but pass. The grid below holds every figure.

Where the break is

Each cell adds the invoices posted to one engine in one month. Click a cell to see the invoices behind it, or click an engine or a month for the whole row or column. A break shows up in the month and engine it sits in, and the two meet at its cell.

Grid shows

Engine by month, System A less the ledger, in thousands of dollars. Amber is outside the limit of $50K.

Scroll the grid sideways to see the later months.

Engine													Year
													+1
													-2
													0
													+200
													+1,151
													-142
													0
													-181
All engines	+1	0	+420	-419	0	-2	+1,150	0	-139	+13	+3	0	+1,027

Behind Engine 5, July

Engine 5, July: System A $2,300K, ledger $1,150K, difference +$1,150K. That is outside the limit.

INV-1033 is loaded twice in System A and once in the ledger. The extra copy moves the break by +$1,150K.

Posted in System A

Invoice	Amount
INV-1033	$1,150K
INV-1033	$1,150K
Total	$2,300K

Posted in the ledger

Invoice	Amount
INV-1033	$1,150K
Total	$1,150K

Field by field

Each field that feeds the report, who owns it, how the two systems are matched, and how it stands at the current limit

Field	Owner	How the two systems match	Tolerance	Result now
Invoice number	Accounts payable	Exact text. Each number should appear once in each system.	None	Break28 of 29 invoice numbers are in both systems. 1 invoice is missing from System A. 1 invoice is loaded more than once in System A.
Engine	Technical records	Exact match once the invoice numbers are paired.	None	Break1 of 28 paired invoices is on a different engine.
Posting month	Fleet accounting	Same calendar month once the invoice numbers are paired.	None, not even one month	Break1 of 28 paired invoices is posted in a different month.
Amount	Fleet accounting	Invoice amounts added up for each engine and month.	$50K on any engine and month	Break7 of 28 paired invoices differ in amount. 6 cells outside the limit, 7 cells within it.
Full-year total	Financial planning and analysis	Every engine and month added up for the year.	$50K on the total	BreakSystem A $7,552K, ledger $6,525K, difference +$1,027K.

One full-year figure is far from the books because one invoice is loaded twice. These steps follow the check from the headline down to the invoice. They read System A as it is loaded, so they ignore the System A switch, and they follow the limit.

What leadership would see
The report reads System A. For the year it shows $7,552K and the ledger shows $6,525K. System A is $1,027K higher, which is 15.7% of the ledger.
Counting lines
System A has 29 lines and the ledger has 29. The counts match, so a count check alone would pass. They match only because 1 extra load in System A offsets 1 missing invoice.
Locate the month
By month, July is furthest out at +$1,150K. 4 of 12 months are outside the limit of $50K.
Locate the engine
By engine, Engine 5 is furthest out at +$1,151K. 4 of 8 engines are outside the limit of $50K.
Find the cell
The largest cell is Engine 5 in July, off by +$1,150K. System A posts $2,300K there and the ledger posts $1,150K. The check flags it.
Find the invoice
Pairing the systems on invoice number explains the cell. INV-1033 is loaded twice in System A and once in the ledger. The extra copy moves the break by +$1,150K.
Fix it and run the check again
Removing the extra load brings System A to $6,402K and the full-year break to -$123K. That is still outside the limit of $50K, so the report stays held until the rest is explained.

A tight limit flags noise. A loose one lets real breaks through. Each row below sets the limit and re-runs the check on the same data.

The vertical axis is the largest break that passed. Teal points are limits where nothing that matters passes. Amber points are limits that let a break of $100K or more through. Each point is one row of the table, so the spacing is not even.

What each limit flags and what it lets through

Limit	Cells flagged	Noise flagged	Real breaks missed	Largest that passed	Full year
Your limit, $50K	6	0	0	$15K	Flagged
$0K	13	7	0	$0K	Flagged
$5K	7	1	0	$3K	Flagged
$10K	7	1	0	$3K	Flagged
$25K	6	0	0	$15K	Flagged
$50K	6	0	0	$15K	Flagged
$100K	6	0	0	$15K	Flagged
$150K	5	0	1	$140K	Flagged
$200K	3	0	3	$185K	Flagged
$500K	1	0	5	$420K	Flagged
$1,000K	1	0	5	$420K	Flagged
$1,100K	1	0	5	$420K	Passes
$1,200K	0	0	6	$1,150K	Passes
$2,500K	0	0	6	$1,150K	Passes

Noise flagged is a flagged cell under $100K. Real breaks missed is a cell of $100K or more that passed. Full year says whether the total for the year is over the limit.

Pairing the two systems on invoice number gives each difference one cause. Some causes move the full-year figure. Others only move an amount between months or engines, so the year looks right and the grid does not.

Blue bars are the two totals. Magenta raises System A above the ledger and teal lowers it. The vertical axis does not start at zero, so the steps can be seen.

Causes, largest first. Amount at issue adds the sizes without signs.

Cause	Invoices	Amount at issue	Effect on the year	What it usually means
Double count in System A	1	$1,150K	+$1,150K	The same invoice came in through two loads. Remove the extra copy from System A.
Missing from System A	1	$140K	-$140K	The invoice has not reached System A yet. Load it.
Amount differs	1	$15K	+$15K	A credit or correction usually reached one system and not the other.
Small amount difference	6	$10K	+$2K	Usually rounding or tax treatment. Normally safe to pass.
Posted in a different month	1	$420K	$0K	The systems date the invoice differently. It cancels out over the year.
Posted to a different engine	1	$185K	$0K	The invoice is coded to a different engine. It cancels out across engines.
All causes	11		+$1,027K	Equals the full-year break of +$1,027K.

Every invoice that differs, largest first

Invoice	What differs	Effect on the year
INV-1033	INV-1033 is loaded twice in System A and once in the ledger. The extra copy moves the break by +$1,150K.	+$1,150K
INV-1009	INV-1009 ($420K) is posted in March in System A and April in the ledger.	$0K
INV-1038	INV-1038 ($185K) is on Engine 4 in System A and Engine 8 in the ledger.	$0K
INV-1037	INV-1037 ($140K, Engine 6, September) is in the ledger and missing from System A.	-$140K
INV-1046	INV-1046 is $40K in System A and $25K in the ledger.	+$15K
INV-1049	INV-1049 is $45K in System A and $42K in the ledger.	+$3K
INV-1023	INV-1023 is $62K in System A and $64K in the ledger.	-$2K
INV-1040	INV-1040 is $34K in System A and $36K in the ledger.	-$2K
INV-1005	INV-1005 is $59K in System A and $58K in the ledger.	+$1K
INV-1017	INV-1017 is $53K in System A and $52K in the ledger.	+$1K
INV-1032	INV-1032 is $72K in System A and $71K in the ledger.	+$1K

The checks run on the current limit and System A setting. A check that cannot fail proves nothing, so the second table breaks the data on purpose and shows which checks go red.

Checks on the numbers above, live

Result	Check	Detail
Pass	Every posting lands in a real engine and month	All postings are placed in the grid.
Pass	The grid adds up to the postings in both systems	System A cells add to $7,552K and ledger cells add to $6,525K.
Pass	The difference is System A less the ledger at every level	117 levels checked: every cell, engine, month and the year.
Pass	Cell differences add to each engine, each month and the year	Engine totals and month totals both add to the full-year break.
Pass	Flagged cells plus passed cells add to the full-year break	+$1,010K flagged plus +$17K passed is +$1,027K.
Pass	A level is flagged only when its difference is over the limit	Flags follow the limit of $50K at all 117 levels.
Pass	The invoice matches add to the full-year break	Causes add to +$1,027K, the same as the break.
Pass	The limit lets nothing that matters through	Nothing of $100K or more passed unflagged.

Broken on purpose

Each fault is added to a copy of the data, and the checks are run again

What was broken	What went red	Result
An invoice dated in a thirteenth month is added to System A	Every posting lands in a real engine and month. The grid adds up to the postings in both systems. The invoice matches add to the full-year break.	Caught
One cell difference is overstated by $100K after it was worked out	The difference is System A less the ledger at every level. Cell differences add to each engine, each month and the year.	Caught
The limit is set at $2,500K, wide enough that nothing is flagged	Nothing that matters passes unflagged.	Caught

A limit of $50K flags 6 cells and holds the report. System A is $1,027K above the ledger for the year. Nothing of $100K or more passed unflagged.