Year

Product

Version

SLOC (Million)

Dev. Estimated Costs (Billion US Dollars)

Maint Estimated

Costs (Billion US Dollars)

2003

Linux 2.6.0

5.2

0.61

1.5

2006

Linux 2.6.8

6.5

1.14

2.7

Oct 2008

Linux 2.6.25

8.2

1.3

3.1

2009

Linux 2.6.29

11.0

1.4

3.7

Dec 2009

Linux 2.6.32

12.6

1.8

4.0

Aug 2010

Linux 2.6.35

13.5

2.4

5.2

July 2011

Linux 3.6

15.9

3.0

6.8