Sign in

Blog · Board and management reporting

Count-weighted and value-weighted: why every ratio on this site says which

The difference between a ratio weighted by count, accounts, deals, inquiries, and one weighted by value, revenue, notional, premium, why the two disagree whenever the large items behave differently from the small ones, the six measures where the difference is largest, hit ratio, coverage, win rate, share of wallet, renewal rate and retention, the rule that a report shows both and ranks by value, and the case where count is the honest one.

The short answerA count-weighted ratio treats every item alike; a value-weighted one lets the large items dominate. They disagree whenever the large items behave differently from the small: a client that trades the small tickets and leaves the large has a high count hit ratio and a low value one; a rep who touches the small accounts and not the big has high count coverage and low revenue coverage. Every ratio on this site states its weighting, shows both where they differ, and ranks by value, because the value is what is at stake. Count is the honest one where the items are genuinely alike, or where the question is about how many relationships.

Every ratio can be computed two ways and the two disagree exactly when it matters: when the large items behave differently from the small ones. This guide sets out count against value weighting, the six measures where the gap is largest, the rule, and the cases where count is right.

The two weightings

Count-weighted Value-weighted
Treats Every item alike Large items as larger
Answers How many? How much?
Hides The large item that behaves differently The many small items
Dominated by The numerous The big

Six measures where the gap is largest

Measure Count version Value version Typical disagreement
Hit ratio Trades ÷ inquiries Notional traded ÷ notional inquired Client takes small tickets, leaves large: 41% vs 15%
Coverage Accounts touched ÷ assigned Revenue of touched ÷ revenue assigned Rep touches the tail: 70% vs 40%
Win rate Won ÷ outcomes Won value ÷ outcome value Large deals lost: 28% vs 21%
Share of wallet, rolled up Mean of customer shares Σ sales ÷ Σ wallets Small customers at extreme shares: 38% vs 30%
Renewal rate Renewed ÷ due Renewed premium ÷ premium due Large renewals lost: 90% vs 84%
Retention Customers retained ÷ start Revenue retained ÷ start revenue Large customers left: 93% vs 89%

The rule

Every ratio states its weighting. Where count and value differ by more than a stated amount, both are shown. The ranking column is value.

Where count is honest

Measure Why count
Count to half The question is how many relationships
Facilities compliant Each facility is a decision
Reps above the data quality floor Each rep is a person
Controls tested on cadence Each control is an obligation

Stated as count, on purpose.

A worked pair

Rep Accounts Touched Coverage by count Revenue assigned Revenue touched Coverage by value
R-04 62 43 69% $4.0m $1.6m 40%
R-11 44 30 68% $3.6m $3.2m 89%

Same count coverage. R-04 touched the tail and not the top; R-11 the reverse. The value column is the finding, and the count column would have called them equal.

The averaging trap

Region roll-up Method Result
Average of rep percentages Count of reps 71%
Σ touched ÷ Σ assigned Accounts 63%
Σ revenue touched ÷ Σ revenue assigned Value 58%

Three numbers for the same region. The first is wrong; the second and third are the two honest ones, and the report shows both.

Where it goes wrong

Weighting unstated. Two people, two ratios, one argument.

Count as the headline. The large item that left, invisible.

Averaged across reps. The eighteen-account rep offsets the sixty-two.

Value where count is the question. Count to half by revenue is not a count.

Every ratio, its weighting

Covirage states the weighting on every ratio, shows both where they differ, and never averages across reps. The size-weighted hit ratio guide covers the sharpest case, and the renewal, retention and churn guide covers three measures on both bases.

Questions people ask

Which should be the headline?

Value, because it is what is at stake, with count beside it. A renewal rate of 90 percent by count and 84 by premium says the renewals lost were the larger ones, and the second number is the one the board should see first.

When is count the right one?

When the items are alike, or when the question is about breadth: how many relationships carry the business, how many facilities are compliant, how many reps are above the floor. Count to half is a count measure by design. The report says which.

What about averages of ratios?

An average of rep percentages is a count-weighted ratio of reps, and it is almost always wrong: the rep with eighteen accounts at 94 percent offsets the one with sixty-two at 53. Roll-ups are weighted by the underlying accounts or value, never averaged across reps.