Complex sentence: Since Saddar does not house a size-able residential population, it has suffered in financial terms from the development of other shopping districts in areas which have a significant residential population as people no longer have to travel to Saddar in order to purchase goods.
Split into simpler sentences: Since Saddar does not house a size-able residential population, it has suffered in financially from the development of other shopping districts, in areas that have a large residential population. As a result, people no longer have to travel to Saddar in order to purchase goods.