Punjab to British East Africa to help build railroads. Sikhs emigrated from India after World War II, most going to the United Kingdom but many also to North America. Some Sikhs who had settled in eastern Africa were expelled by Ugandan dictator Idi Amin in 1972. Economics is a major factor in Sikh migration, and significant communities exist in the United Kingdom, the United States, Malaysia, East Africa, Australia, Singapore and Thailand. After the Partition of India in 1947, many Sikhs from what would become the Punjab of Pakistan migrated to India as well as to Afghanistan due to fear of persecution. Afghanistan was home to hundreds of thousands of Sikhs and Hindus as of the 1970s, but due to the wars in Afghanistan in the 2010s, the vast majority of Afghan Sikhs had migrated to India, Pakistan or the west. Although the rate of Sikh migration from the Punjab has remained high, traditional patterns of Sikh migration favouring English-speaking countries (particularly the United Kingdom) have changed during the past decade due to stricter immigration laws. Moliner (2006) wrote that as a consequence of Sikh migration to the UK becoming "virtually impossible since the late 1970s," migration patterns evolved to continental Europe. Italy is a rapidly growing destination for Sikh migration, with Reggio Emilia and Vicenza having significant Sikh population clusters. Italian Sikhs are generally involved in agriculture, agricultural processing, the manufacture of machine tools, and horticulture. Growth Johnson and Barrett (2004) estimate that the global Sikh population increases annually by 392,633 (1.7% per year, based on 2004 figures); this percentage includes births, deaths, and conversions. Primarily for socio-economic reasons, Indian Sikhs have the lowest adjusted growth rate of any major religious group in India, at 16.9 percent per decade (estimated from 1991 to 2001) and it have further declined to just 8.4 per cent in 2011 census report. Sikhs in the world have the lowest fertility rate of 1.6 children per women as per (2019–20) estimation research. The Sikh population has the lowest gender balance in India, with only 903 women per 1,000 men according to the 2011 Indian census. The estimated world's Sikh population was over 30 million in 2020, and it will reach 42 million by 2050. It is expected to increase up to 62 million by 2100, given that the anticipated growth rate of 1.7% per year and adding at least 400,000 followers annually. Sikhism is