June 27, 2007 (LPAC) -- A new report from Standard & Poor's finds a sharp rise in late payments and defaults on Alt-a mortgage loans, those between prime and subprime, for which borrowers do not provide full documentation of income and assets.

Some 4.21% of Alt-a loans bundled into mortgage-backed securities last year were 90 or more days overdue after 14 months, up sharply from 1.59% for loans from 2005 and 0.91% for loans from 2004.