Is this very common?

[#1]

ADSL Link                Downstream            Upstream
Connection Speed    15313 kbps                883 kbps
Line Attenuation                28 db                    7 db
Noise Margin                        1 db                10 db
Just asking out of curiosity, I have never seen the noise margin this low before although everything seems to be working ok.
Router is a Neatgear DG834G v3
Been running routerstats for 20 mins and the noise margin has been steady at 1db, just how much if any margin do you need?
Len

[#2]

I've got the same model, and it is apparently notorious for not reporting noise level correctly. I've had mine show negative numbers before now.