gender disparity (the difference between female and male literacy rates) was 15.13%. As per 2001 census, Salanpur block had a total literacy of 78.22 per cent for the 6+ age group. While male literacy was 87.07 per cent female literacy was 68.20 per cent. Bardhaman district had a total literacy of 70.18 per cent, male literacy being 78.63 per cent and female literacy being 60.95 per cent. See also – List of West Bengal districts ranked by literacy rate Language and religion As per census definition, mother-tongue is the language spoken in childhood by the person's mother to the person. As a mother-tongue, Bengali has decreased its share from 82.3% of the population of Bardhaman district in 1961 to 79.9% in 2001, Hindi has increased its share from 8.5% in 1961 to 10.9% in 2001 Santali has remained steady at around 4.9% during the period, and Urdu has increased its share from 2.4% in 1961 to 2.6% in 2001. Other mother-tongues spoken in 2001 were: Odiya (0.3%), Punjabi (0.2%), Koda/Kora (0.2%), Telugu (0.1%), Bhojpuri (0.1%), Nepali (0.1%) and Kurukh/ Oraon (0.1%). As of 2017, CD Block-wise/ other region-wise break-up of mother tongue is not available in census/ other official sources. There have been reports in the media about the Hindi speaking population being substantial in the Asansol (Lok Sabha constituency). Bardhaman district provided attractive livelihood opportunities for immigrants from Bihar/ Jharkhand. According to the West Bengal Official Language Act 1961 and the West Bengal Official Language (Amendment Act) 2012, the Bengali language is to be used for official purposes in the whole of West Bengal. In addition to Bengali, the Nepali language is to be used for official purposes in the three hills subdivisions, namely Darjeeling, Kalimpong and Kurseong, in the district of Darjeeling, and Urdu is to be used for official purposes in district/subdivision/ block/ municipality where the population speaking Urdu exceeds 10% of the total population. The English language will continue to be used for official purposes as it was being used prior to the enactment of these laws. The West Bengal Official Language (Second Amendment) Bill, 2012, included Hindi, Santhali, Odiya and Punjabi as official languages if it is spoken by a population exceeding 10 per cent of the whole in a particular block or sub-division or a district. Subsequently, Kamtapuri, Rajbanshi and Kurmali were also included in the list of minority languages by the West Bengal