Mere bhai in the article it mentions " lilelihood of terror attacks based on historic trends"
Obviously they must have defined what a terrorist attack constitutes before analyzing the data. And most possibly they did not consider sectarian, ethnic or target killing as constituting terror attack
Just an interesting fact for u guys:
Musharrafs family is originally from Ludhiana. Old delhi had a lot of punjabi muslims, specially from east punjab before 1857. They had contributed financially towards the rebel cause in 57 and were as a result deported when the british took back Delhi