The number of immigrants needed during different stages of the economic cycle could be controlled by varying the subsidy. Before federation in 1901, assisted migrants received passage assistance from colonial government funds; the British government paid for the passage of convicts, paupers, the military and civil servants. Few immigrants received colonial government assistance before 1831. In Queensland many immigrants passed through the Yungaba Immigration Centre in Brisbane. The facility was built shortly after a period when immigration had been at an all-time high.