Boosted by fatter warehousing spreads and sweeter secondary market gains on loan sales, mortgage banking profits rose handsomely in 2002, according to detailed financial data reported recently by the Mortgage Bankers Association. In its latest annual cost study, covering data from 2002 financial reports, the MBA analysis finds that average pre-tax profits rose from $23.2 million in 2001 to $40.4 million last year. This “net financial income” figure includes the amortized cost of servicing,