Originations of non-agency jumbo mortgages increased by 19.4 percent in 2012 compared with the previous year, according to affiliated publication Inside Mortgage Finance. The sector is expected to continue to grow as jumbos are increasingly attractive for bank portfolios and securitization. An estimated $203.0 billion in non-agency jumbo mortgages were originated in 2012, marking the third straight year of increased production. The sector is driven by big banks ... [Includes one data chart]