[originaltext] (3) The Australian population is expected to reach 24 million

(3) The Australian population is expected to reach 24 million at 12 :51 am on Tuesday, (4) with more than half of that growth driven by new migrants.  With the arrival of this historic moment, Australia will draw level with Shanghai, which houses 24 million people. The latest population figure is drawn from the Australian Bureau of Statistics population clock, which shows a predicted rate of population growth based on 12-monthly population estimates.
    It anticipates a population increase of one person every 91 seconds, based on known birth, death and migration rates. Based on these rates Australia will reach a population of 25 million in 2018 and 50 million in 2086. By then the global population will have reached 10. 6 billion, according to UN forecasts based on medium predicted birth rates.
    (4) An ABS official said overseas migration counted for 54% of Australia’s growth in 2015, according to actual migration figures drawn from passenger cards filled in at the country’s international airports.
3. What’s the news mainly about?
4. How has the present situation arisen?