Complex sentence: Although purpose built software does exist, the vast proportion of the market is spreadsheet-based--this is largely since the models are almost always company specific; also, analysts will each have their own criteria and methods for financial modeling.
Split into simpler sentences: Although purpose built software does exist, the vast proportion of the market is spreadsheet-based; this is largely since the models are almost always company specific. Aso, analysts will each have their own criteria and methods for financial modeling.