The Philippine Trade department is continuously monitoring cement prices and could still revise an earlier decision slashing cement duties to P15.60 from P20.60 per 40-kilogram bag.  Trade and Industry Sec. Cesar A.V. Purisima said the government is keen on striking a balance between the needs of the industry and consumers, noting that the new duty rates are only temporary.  "There is nothing permanent and everything is being reviewed. We will continue the review because market conditions change," Mr. Purisima said.  He issued the statement after cement manufacturers expressed disappointment over the Department of Trade and Industry's (DTI) lowering of import taxes on cement last December.