Please answer a question about the following article about British Empire:

Since 1718, transportation to the American colonies had been a penalty for various criminal offences in Britain, with approximately one thousand convicts transported per year across the Atlantic. Forced to find an alternative location after the loss of the 13 Colonies in 1783, the British government turned to the newly discovered lands of Australia. The western coast of Australia had been discovered for Europeans by the Dutch explorer Willem Jansz in 1606 and was later named New Holland by the Dutch East India Company, but there was no attempt to colonise it. In 1770 James Cook discovered the eastern coast of Australia while on a scientific voyage to the South Pacific Ocean, claimed the continent for Britain, and named it New South Wales. In 1778, Joseph Banks, Cook's botanist on the voyage, presented evidence to the government on the suitability of Botany Bay for the establishment of a penal settlement, and in 1787 the first shipment of convicts set sail, arriving in 1788. Britain continued to transport convicts to New South Wales until 1840. The Australian colonies became profitable exporters of wool and gold, mainly because of gold rushes in the colony of Victoria, making its capital Melbourne the richest city in the world and the largest city after London in the British Empire.

How many convicts per year had Britain been sending to the American colonies?
one thousand