In the early 20th century, the Dutch colony of Java became a leading exporter of coca leaf. By 1912 shipments to Amsterdam, where the leaves were processed into cocaine, reached 1000 tons, overtaking the Peruvian export market. Apart from the years of the First World War, Java remained a greater exporter of coca than Peru until the end of the 1920s. Other colonial powers also tried to grow coca (including the British in India), but with the exception of the Japanese in Formosa, these were relatively unsuccessful.