From the meaning of the question: let's assume that the output value in 2006 is X yuan, then:

20 1 1 year: x plus 36% x =136% x =1.36x.

20 12: X plus 48% x =148% x =1.48x.

Compared with 20 1 1 year, 20 12 year increased:1.48x-1.36x = 0.12x.

= 12%x

Average value during 20/200612: 0.48 x/x \u( 20 12-2006).

=48%÷6=8%

You can ask if you don't understand.

I wish you progress in your study!