Opaindex
Contract escalation calculator
To escalate a Nigerian construction contract for materials-price movement, multiply the contract value by the ratio of the Building Materials Cost Index now (100.0) to its level on the award date. The Opaindex index is base 100 on 26 June 2026, so a fully materials-linked contract awarded then is worth 0.0% more today — a factor of 1.0000.
Key takeaways
- Escalation = contract value × the change in the Building Materials Cost Index between the award date and now.
- The index is 100.0 today (base 100 on 26 June 2026); freshest reading 26 June 2026.
- Apply the index only to the materials-linked proportion of the contract; the rest is treated as fixed.
- It runs in your browser against the sourced index — no figure is invented. A reference computation, not legal advice.
₦10,000,000 → ₦10,000,000
escalation of ₦0 (0.0%) at an index factor of 1.0000 · 26 June 2026
New value = contract value × [ (1 − m) + m × (index now ÷ index at award) ], where m is the materials-linked proportion. The calculator runs entirely in your browser against the index level below.
Worked examples
Contracts awarded on the 26 June 2026 index launch (level 100), fully materials-linked, escalated to today's index of 100.0 — a factor of 1.0000.
| Contract value at award | Escalated value now | Escalation amount |
|---|---|---|
| ₦1,000,000 | ₦1,000,000 | +₦0 |
| ₦5,000,000 | ₦5,000,000 | +₦0 |
| ₦10,000,000 | ₦10,000,000 | +₦0 |
| ₦50,000,000 | ₦50,000,000 | +₦0 |
| ₦100,000,000 | ₦100,000,000 | +₦0 |
The index is at its 100 base, so no materials-price escalation has accrued since launch yet. As tracked prices move, the factor above moves with them.
How escalation is calculated
A construction price-fluctuation (escalation) clause adjusts a contract by the change in a cost index between the award date and the valuation date. The standard single-index form is:
where m is the materials-linked proportion of the contract. With m = 100% it reduces to Base × (Indexnow ÷ Indexaward). This calculator uses the Opaindex Building Materials Cost Index for both index values — a fixed reference bill of core Nigerian materials re-priced at tracked, sourced prices, base 100 on 26 June 2026.