From 2000 to 2008, commercial mortgage modifications were relatively unheard of. It was a different story in 2009 and 2010. Of all loan modifications in the commercial mortgage industry over the past decade, 96% occurred in the last years, according to Standard & Poor's. The rating agency said 354 commercial real estate loans with a principal balance $15.6 billion were modified from January through November, up significantly from 216 loans valued at $7.06 billion for all of 2009. Analysts said extending maturities on commercial mortgages has been the most common loan modification in the space since 1998. "Our view is that extending maturities for loans with stable cash flows has helped keep trust expenses down and has prevented higher losses typically associated with property liquidations at distressed prices," Standard & Poor's credit analyst Larry Kay said. The agency said loan modifications in commercial real estate possibly helped keep mortgage delinquencies down last year. Analysts expect modifications to remain high in 2011, although liquidations are projected "to increase as a percentage of total resolutions as market conditions improve," according to S&P credit analyst Louis Cicerchia. Modifications to prevent liquidations in the commercial mortgage market is know as the "extend and pretend" strategy. The rating agency said mortgage modifications help limit defaults by giving borrowers options, "especially those that have struggled to secure refinancing for upcoming loan maturities." In late December, analytics firm Trepp warned investors of severe losses within two commercial mortgage-backed securities deals due to loan modifications and note sales. Earlier this week, Trepp said the delinquency rate on CMBS rose to 9.2% in December, the highest on record. Following a drop in delinquencies with CMBS in October, analysts started projecting a recovery, but the rate jumped 35 basis points in November and another 27 basis points last month. Write to Jason Philyaw.