Most merchants who start selling on installments track exactly one number: total sales. It goes up, so the programme looks like a success. Six months later the shelves have moved but the bank account has not, and nobody can say which customers are behind or by how much.

Here are the five numbers that actually tell you whether installment selling is working.

1. Collected, not contracted

The value of agreements you have signed is not revenue. It is a promise.
The rule: Track contracted value and collected value as two separate lines, side by side. The gap between them is your exposure. If that gap grows faster than collections, you are financing your customers, not selling to them.

2. On-time rate per plan type

Weekly, bi-weekly and monthly plans behave very differently. Measure each separately.

• If weekly wins: Your customers are paid weekly too , match the schedule to their income, not to your accounting calendar.

• If monthly lags: The installment is probably too large relative to income. Splitting the same total across more, smaller payments usually raises the on-time rate more than any reminder ever will.

3. Days-to-first-default

Track how many days pass between signing and the first missed payment. A short average means your approval step is too loose , the trust score check is being skipped or overridden. A long average means defaults are life events, not credit decisions, and are better handled by rescheduling than by escalation.

4. Recovery rate, measured honestly

Recovery rate is collected value divided by contracted value on agreements that have fully matured.

• Do not include agreements still inside their term , that flatters the number.

• Do not count rescheduled agreements as recovered until the new schedule is actually paid.

• A recovery rate you can defend to a lender is worth more than a flattering one you cannot. It is the number that eventually determines what credit you yourself can access.