Nominal and real non-oil shares

Consider a hypothetical economy containing only oil and non-oil production, with no separate tax or government adjustment. At initial prices, oil value added is 400 and non-oil value added is 600. Total value added is 1,000, and the non-oil share is 60 percent.

Now reduce the oil price by 25 percent, keeping oil volume, non-oil prices and non-oil volume unchanged. Oil value added in this simplified model falls to 300; non-oil value remains 600. The non-oil share becomes:

$$600/(300+600)=66.67\%.$$

The nominal share rises by 6.67 percentage points without any non-oil volume growth. This example treats sector values as price times a fixed volume for transparency. It is not a reconstruction of either country's actual production accounts, which require a fuller treatment of output and intermediate inputs.

In a further hypothetical step, allow non-oil volume to rise by 5 percent at its unchanged price. Its value becomes 630. With oil value still at 300, the nominal non-oil share is approximately 67.74 percent. At the original common prices, however, the corresponding ratio is 630/(400 + 630), or approximately 61.17 percent. Different price bases produce different share movements.

The illustration uses a single compatible price basis deliberately. Published chain-linked sector levels may not add to chain-linked GDP outside the relevant reference conditions. Dividing such a component by a separately linked total can create a ratio that lacks the simple additive interpretation of a current-price share.

For a statement about economic structure at prevailing prices, use consistent current-price values and the published denominator. For a statement about real expansion, use the sector's volume growth and the appropriate contribution measures. A fixed-price structural comparison can be constructed only with a defensible common-price method and explicit qualifications.

Classification is another source of difference. Refining, petrochemicals, utilities and government services may be grouped differently across statistical presentations. A comparison of Saudi Arabia and the UAE should identify the actual activities included, the treatment of taxes and the vintage of the accounts. A change in classification can alter the share without changing the underlying production.

A sustained rise in non-oil output can indicate broader domestic production, but a nominal share alone cannot establish export diversification, fiscal resilience or a reduced dependence on oil-related income. Those questions concern different transactions and transmission channels.

For example, a domestic service can be classified outside oil while its customers' spending remains sensitive to oil revenue. Establishing that dependence requires expenditure or income evidence; the classification itself supplies no causal estimate.

A useful diversification assessment therefore reports the nominal share, real non-oil growth, relevant contributions and the accounting definition together. It explains how relative prices affected the headline before interpreting the remainder as structural change. That separation preserves the information in the share while preventing an oil-price movement from being mistaken for newly created non-oil capacity.