Here's some interesting data from Wikipedia:
"The population of the province is estimated to be 86,084,000 in 2005 and is home to over half the population of Pakistan. The major language spoken in the Punjab is Punjabi (which is written in Perso-Arabic script, known as Shahmukhi, in Pakistan) and Punjabis comprise the largest ethnic group (and overlap into neighbouring India). Punjabis themselves are a heterogeneous group comprising different tribes and communities, although caste in Pakistani Punjab has more to do with traditional occupations such as blacksmiths or artisans as opposed to rigid social stratifications.
"The most important tribes within Punjab include the Gakhars, Jats, the Arain, the Gujjars and the Rajputs. Other smaller tribes are the: Awans, Rawns, and Maliks. In addition, there is a significant shift towards the usage of Urdu by the educated classes of the province as the Punjabis are the most ardent supporters of the nation-state of Pakistan and all of its national institutions. There is also a nationalist movement amongst the somewhat related Seraikis in the south of Punjab and many wish to see a separate the region into a new province of Seraikistan. Other smaller groups in the province include Hindko, Pakhtuns, Balochs, Kashmiris and others.
"The population of Punjab(Pakistan) is over 99% Muslim with a Sunni majority and Shia minority. There are small non-Muslims groups of Hindus, Christians, and Sikhs.
"The religious demographics pre-1947 were radically different owing to the mass exchange of populations at the time of partition . There were substantial populations of Hindus and Sikhs in all districts which went on to become part of Punjab(Pakistan )."
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