Why don't the trade figures reported by SBP in the balance of payments match with the information provided by the Pakistan Bureau of Statistics (PBS)? This question is often raised at various levels, particularly among students of economics and finance.
Here is a single answer: According to State Bank of Pakistan, this is due to the fact that the trade statistics compiled by SBP are based on exchange record data, which depend on the actual receipt and payment of foreign exchange, whereas the PBS records data on the physical movement of goods (customs record). Further more, SBP reports both exports and imports as free on board (fob), while PBS records exports as free on board (fob) and imports include the cost of freight and insurance (cif).
In addition, the variation in import data also arise due to differences in data coverage, eg., SBP import data does not include Non-Repatriable Investments (NRI) by non-resident Pakistanis, imports under foreign assistance, land-borne imports with Afghanistan, etc. In export data, these differences emerge as PBS statistics do not take into account short shipments and cancellations, while SBP data does not take into account land-borne exports to Afghanistan, export samples given to prospective buyers by exporters, exports by EPZs, etc. Hence, they need a right approach to trade statistics by fully appreciating the mechanisms employed by both SBP and PBS in relation to foreign trade figures.