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Blog · Board and management reporting

Contribution on ten accounts: the whole arithmetic on one page

The complete contribution-after-cost-to-serve calculation on ten accounts small enough to check by hand: revenue and cost per account from invoice lines, gross margin, drops, returns and pick lines from the delivery log at stated rates, cost to serve, contribution and contribution rate, the revenue rank against the contribution rank, the components behind the account that drops furthest, and the identity that account margins sum to the ledger's gross margin, so a reader can reproduce every figure and then run it on their own exports.

The short answerTen accounts with revenue and cost of goods from the invoice lines, and drops, returns and pick lines from the delivery log. Cost to serve is drops at $60, returns at value plus $15 handling each, and pick lines at $0.80, all stated. Contribution is gross margin less cost to serve. Ranked, the second-largest account by revenue is ninth by contribution, because it takes daily drops and returns a tenth of what it buys, and a fifth-ranked account is first. The account margins sum to the ledger's gross margin, and every number can be reproduced by hand.

Contribution is gross margin less what it costs to serve the account, and on ten accounts the whole calculation fits on a page. This page works it: margin from the invoice lines, cost to serve from the delivery log at stated rates, the two rankings, the components, and the identity.

The rates, stated

Component Rate
Drop $60 per delivery
Return Returned value + $15 handling per return
Pick line $0.80 per invoice line

The accounts, from the invoice lines

Account Revenue Cost of goods Gross margin Margin %
A $420,000 $357,000 $63,000 15.0%
B $380,000 $310,000 $70,000 18.4%
C $310,000 $272,000 $38,000 12.3%
D $180,000 $148,000 $32,000 17.8%
E $150,000 $118,000 $32,000 21.3%
F $90,000 $71,000 $19,000 21.1%
G $75,000 $61,000 $14,000 18.7%
H $60,000 $50,000 $10,000 16.7%
I $40,000 $32,000 $8,000 20.0%
J $25,000 $21,000 $4,000 16.0%
Total $1,730,000 $1,440,000 $290,000 16.8%

Ledger gross margin for these accounts: $290,000. Identity holds.

Cost to serve, from the delivery log

Account Drops Drop cost Returns (count, value) Return cost Lines Line cost Cost to serve
A 260 $15,600 12, $9,000 $9,180 3,100 $2,480 $27,260
B 104 $6,240 4, $2,000 $2,060 1,900 $1,520 $9,820
C 250 $15,000 40, $31,000 $31,600 2,800 $2,240 $48,840
D 52 $3,120 2, $1,000 $1,030 900 $720 $4,870
E 48 $2,880 3, $1,500 $1,545 700 $560 $4,985
F 52 $3,120 1, $400 $415 500 $400 $3,935
G 24 $1,440 0 $0 300 $240 $1,680
H 104 $6,240 6, $3,000 $3,090 800 $640 $9,970
I 12 $720 0 $0 200 $160 $880
J 24 $1,440 1, $200 $215 150 $120 $1,775

Contribution and the two rankings

Account Revenue rank Gross margin Cost to serve Contribution Rate Contribution rank
A 1 $63,000 $27,260 $35,740 8.5% 2
B 2 $70,000 $9,820 $60,180 15.8% 1
C 3 $38,000 $48,840 −$10,840 −3.5% 10
D 4 $32,000 $4,870 $27,130 15.1% 3
E 5 $32,000 $4,985 $27,015 18.0% 4
F 6 $19,000 $3,935 $15,065 16.7% 5
G 7 $14,000 $1,680 $12,320 16.4% 6
H 8 $10,000 $9,970 $30 0.1% 9
I 9 $8,000 $880 $7,120 17.8% 7
J 10 $4,000 $1,775 $2,225 8.9% 8

Account C, third by revenue, loses money. Account H, eighth by revenue, breaks even on twice-weekly drops and a five percent return rate.

The components behind C

Component Cost Lever
250 drops, five a week $15,000 Two drops a week saves $8,760
40 returns, $31,000 $31,600 A returns policy; the returns are a tenth of revenue
2,800 lines $2,240 A minimum line value

The returns are the finding, and the account manager has the number.

Where it goes wrong, even at ten

Revenue as the ranking. C is a top-three account.

Cost to serve averaged. Every account at $11,400; C's contribution reads $26,600 and the ranking is the revenue ranking.

Rates unstated. C's account manager disputes the $60.

Contribution floored. C reads zero and the size of the loss is lost.

From ten to ten thousand

The same components per account from the delivery log and credits, at the same stated rates. Covirage runs it on the invoice lines and the delivery log every quarter. The margin by account guide covers the measure, and the cost to serve by industry hub covers the components on other desks.

Questions people ask

Where do the rates come from?

The company's own cost per drop, per return handled and per line picked, computed once a year from the delivery and warehouse cost base, and stated on the report. They are approximate; the ranking is stable across a wide range of them, and they are the same for every account.

Why floor nothing here?

Contribution can be negative, and on this page one account is. A negative contribution is a fact about the account's cost to serve, and the components say which lever changes it. It is not floored, because the size of the loss is the argument.

What does the identity check?

That the ten gross margins sum to the ledger's gross margin for these accounts, so that no line is missing its cost. A line with no cost would inflate that account's margin and break the sum.