Global DRAM sales are expected to increase to $33.7bn in 2013, an increase of 28% from a year earlier, according to a report from IC Insights.

However, IC Insights said the capital expenditures in the world’s DRAM business for 2013 is expected to fall to $4bn from $5.1bn spent in 2012.

The company noted that the 2013 capital expenditures spending is anticipated to account for only 11.9% of the market’s total sales, the lowest ratio in the sector’s history.

IC Insights said the ability of suppliers to invest more money to build a new wafer fab or to upgrade existing fabs has become nearly prohibitive for all but the leading DRAM manufacturers.

The report noted that with the price of a new wafer fab approaching $5bn, only Samsung, SK Hynix, and the new Micron-Elpida will be able to continue investing in new and/or upgraded facilities in 2013.

From 2010-2013, Samsung’s cumulative four-year DRAM capital spending was $10.95bn and it is expected to exceed the amount spent by either of its rivals, SK Hynix, with $6.1bn and Micron with $5.1bn over the same period.

The report said in the five-year span from 2004-2008, DRAM capital expenditures as a percent of sales averaged 42.1% and the ratio over the five-year span from 2009-2013 is forecast to average 21.5%.