The output value of fertilisers is derived using the following fob prices as reference prices: Urea (HS 31102.10) for nitrogen, DAP (HS 3105.30) for phosphorus, and MOP (HS 3104.20) for potassium (Figure A.3). Bilateral tariff data obtained from the 2007 MacMap database for Urea, DAP and MOP, serve as reference bilateral tariffs for nitrogen, phosphorus and potassium, respectively. The production technology for the three fertiliser sectors is derived from IFA (2013b). The rest of the chemicals sector is then calculated residually.